class User:
    def __init__(self, username, password):
        self.username = username
        self.password = password
        self.following = []
        self.posts = []
        
    def follow(self, user):
        self.following.append(user)
        
    def post(self, post):
        self.posts.append(post)
        
    def get_feed(self):
        feed = []
        for user in self.following:
            feed += user.posts
        return feed
    
class Post:
    def __init__(self, caption, image_path):
        self.caption = caption
        self.image_path = image_path
        
    def __repr__(self):
        return f"{self.caption} ({self.image_path})"
        
class ImageProcessor:
    @staticmethod
    def resize(image_path, size):
        # resize the image and save it to the same path
        pass
        
    @staticmethod
    def filter(image_path, filter):
        # apply the filter to the image and save it to the same path
        pass
        
class NotificationService:
    def notify(self, user, message):
        # send a notification to the user
        pass
        
class Instagram:
    def __init__(self):
        self.users = []
        self.image_processor = ImageProcessor()
        self.notification_service = NotificationService()
        
    def sign_up(self, username, password):
        user = User(username, password)
        self.users.append(user)
        return user
        
    def post(self, user, caption, image_path):
        image_processor.resize(image_path, (1024, 1024))
        post = Post(caption, image_path)
        user.post(post)
        self.notify_followers(user, post)
        
    def notify_followers(self, user, post):
        message = f"{user.username} posted a new photo: {post}"
        for follower in user.following:
            self.notification_service.notify(follower, message)
            
instagram = Instagram()

alice = instagram.sign_up("alice", "password123")
bob = instagram.sign_up("bob", "password456")
charlie = instagram.sign_up("charlie", "password789")

alice.follow(bob)

bob.post("Here's a photo", "bob_photo.jpg")

feed = alice.get_feed()
print(feed)  # [Here's a photo (bob_photo.jpg)]

import requests
import json

# Define the Instagram API endpoint
base_url = 'https://graph.instagram.com/'

# Define the access token for the API
access_token = '<YOUR_ACCESS_TOKEN_HERE>'

# Define the endpoint for the user's feed
feed_endpoint = f'{base_url}me/media?fields=id,caption,media_type,media_url,permalink,thumbnail_url,timestamp&access_token={access_token}'

# Define the function to retrieve the user's Instagram feed
def get_feed():
    # Send a GET request to the feed endpoint
    response = requests.get(feed_endpoint)

    # Decode the response as JSON
    data = json.loads(response.text)

    # Extract the relevant data from the response
    feed = []
    for post in data['data']:
        feed_item = {
            'id': post['id'],
            'caption': post.get('caption', {}).get('text', ''),
            'media_type': post['media_type'],
            'media_url': post['media_url'],
            'permalink': post['permalink'],
            'thumbnail_url': post['thumbnail_url'],
            'timestamp': post['timestamp']
        }
        feed.append(feed_item)

    return feed

import requests

# Define the Instagram API endpoint
base_url = 'https://graph.instagram.com/'

# Define the access token for the API
access_token = '<YOUR_ACCESS_TOKEN_HERE>'

# Define the function to like a post
def like_post(post_id):
    # Define the endpoint for liking a post
    like_endpoint = f'{base_url}{post_id}/likes'

    # Send a POST request to the like endpoint
    response = requests.post(like_endpoint, params={'access_token': access_token})

    # Check the response status code
    if response.status_code == 200:
        print('Post liked successfully!')
    else:
        print('Unable to like post.')

import requests

# Define the Instagram API endpoint
base_url = 'https://graph.instagram.com/'

# Define the access token for the API
access_token = '<YOUR_ACCESS_TOKEN_HERE>'

# Define the function to follow a user
def follow_user(user_id):
    # Define the endpoint for following a user
    follow_endpoint = f'{base_url}{user_id}/follow'

    # Send a POST request to the follow endpoint
    response = requests.post(follow_endpoint, params={'access_token': access_token})

    # Check the response status code
    if response.status_code == 200:
        print('User followed successfully!')
    else:
        print('Unable to follow user.')

import java.util.*;

class User {
    private String userId;
    private String username;
    private String password;
    // other user attributes
    
    public User(String userId, String username, String password) {
        this.userId = userId;
        this.username = username;
        this.password = password;
        // initialize other attributes
    }
    
    // Getters and setters for attributes
    // ...
}

class Post {
    private String postId;
    private User user;
    private String caption;
    // other post attributes
    
    public Post(String postId, User user, String caption) {
        this.postId = postId;
        this.user = user;
        this.caption = caption;
        // initialize other attributes
    }
    
    // Getters and setters for attributes
    // ...
}

class Instagram {
    private Map<String, User> users;
    private List<Post> posts;
    
    public Instagram() {
        this.users = new HashMap<>();
        this.posts = new ArrayList<>();
    }
    
    public void addUser(User user) {
        users.put(user.getUserId(), user);
    }
    
    public User getUserById(String userId) {
        return users.get(userId);
    }
    
    public void createPost(String userId, String caption) {
        User user = getUserById(userId);
        
        if (user == null) {
            System.out.println("User not found");
            return;
        }
        
        String postId = generatePostId(); // Generate a unique post ID
        Post post = new Post(postId, user, caption);
        posts.add(post);
        
        // Additional logic to update user's feed, notify followers, etc.
        // ...
    }
    
    public List<Post> getFeed(String userId) {
        List<Post> userFeed = new ArrayList<>();
        
        for (Post post : posts) {
            if (post.getUser().getUserId().equals(userId)) {
                userFeed.add(post);
            }
        }
        
        return userFeed;
    }
    
    // Additional methods for handling likes, comments, follow/unfollow, etc.
    // ...
}

public class Main {
    public static void main(String[] args) {
        Instagram instagram = new Instagram();
        
        User user1 = new User("1", "Alice", "password");
        User user2 = new User("2", "Bob", "password");
        
        instagram.addUser(user1);
        instagram.addUser(user2);
        
        instagram.createPost("1", "Hello, world!");
        
        List<Post> user1Feed = instagram.getFeed("1");
        for (Post post : user1Feed) {
            System.out.println("User: " + post.getUser().getUsername());
            System.out.println("Caption: " + post.getCaption());
            System.out.println();
        }
    }
}

from flask import Flask, request

app = Flask(__name__)

# sample data to be stored in the server
users = {
    "user1": {
        "name": "John Doe",
        "followers": ["user2", "user3"],
        "following": ["user2", "user3"],
        "posts": [
            {
                "id": 1,
                "caption": "This is my first post!",
                "image_url": "https://example.com/images/post1.jpg",
                "timestamp": "2022-02-18 14:30:00"
            },
            {
                "id": 2,
                "caption": "Another post!",
                "image_url": "https://example.com/images/post2.jpg",
                "timestamp": "2022-02-18 14:35:00"
            }
        ]
    },
    "user2": {
        "name": "Jane Doe",
        "followers": ["user1"],
        "following": ["user1"],
        "posts": [
            {
                "id": 3,
                "caption": "Hello world!",
                "image_url": "https://example.com/images/post3.jpg",
                "timestamp": "2022-02-18 14:40:00"
            }
        ]
    },
    "user3": {
        "name": "Bob Smith",
        "followers": ["user1"],
        "following": ["user1"],
        "posts": []
    }
}

# endpoint for retrieving a user's information
@app.route('/users/<username>', methods=['GET'])
def get_user(username):
    if username in users:
        return users[username], 200
    else:
        return "User not found", 404

# endpoint for following a user
@app.route('/users/<follower>/follow/<following>', methods=['POST'])
def follow_user(follower, following):
    if follower in users and following in users:
        if following not in users[follower]['following']:
            users[follower]['following'].append(following)
            users[following]['followers'].append(follower)
        return "User followed", 200
    else:
        return "User not found", 404

# endpoint for unfollowing a user
@app.route('/users/<follower>/unfollow/<following>', methods=['POST'])
def unfollow_user(follower, following):
    if follower in users and following in users:
        if following in users[follower]['following']:
            users[follower]['following'].remove(following)
            users[following]['followers'].remove(follower)
        return "User unfollowed", 200
    else:
        return "User not found", 404

# endpoint for creating a post
@app.route('/users/<username>/posts', methods=['POST'])
def create_post(username):
    if username in users:
        caption = request.json.get('caption')
        image_url = request.json.get('image_url')
        timestamp = request.json.get('timestamp')
        post_id = len(users[username]['posts']) + 1
        post = {"id": post_id, "caption": caption, "image_url": image_url, "timestamp": timestamp}
        users[username]['posts'].append(post)
        return "Post created", 200
    else:
        return "User not found", 404

# endpoint for retrieving all posts from followed users
@app.route('/users/<username>/feed', methods=['GET'])
def get_feed(username):
    if username in users:
        feed = []
        for user in users[username]['following']:
            feed.extend(users[user]['posts'])
        sorted_feed = sorted(feed, key=lambda post: post['timestamp'], reverse=True)
        return {"feed": sorted_feed}, 200
    else:
        return "User not found", 404

from flask import Flask, request

app = Flask(__name__)

# Hardcoded list of users for demonstration purposes
users = [
    {
        "id": 1,
        "username": "johndoe",
        "email": "[email protected]",
        "password": "password123",
        "bio": "I love photography and exploring the world!",
    }
]

# Endpoint for creating a new account
@app.route("/users", methods=["POST"])
def create_user():
    data = request.get_json()
    new_user = {
        "id": len(users) + 1,
        "username": data["username"],
        "email": data["email"],
        "password": data["password"],
        "bio": "",
    }
    users.append(new_user)
    return {"message": "User created successfully"}, 201

# Endpoint for logging in
@app.route("/login", methods=["POST"])
def login():
    data = request.get_json()
    for user in users:
        if user["username"] == data["username"] and user["password"] == data["password"]:
            return {"message": "Login successful"}, 200
    return {"message": "Login failed"}, 401

# Endpoint for updating profile information
@app.route("/users/<int:user_id>", methods=["PATCH"])
def update_user(user_id):
    data = request.get_json()
    for user in users:
        if user["id"] == user_id:
            user["bio"] = data["bio"]
            return {"message": "Profile updated successfully"}, 200
    return {"message": "User not found"}, 404

# Endpoint for retrieving profile information
@app.route("/users/<int:user_id>", methods=["GET"])
def get_user(user_id):
    for user in users:
        if user["id"] == user_id:
            return user, 200
    return {"message": "User not found"}, 404

// Endpoint for uploading a new photo
POST /photos
{
    "image_url": "https://s3.amazonaws.com/instagram-photos/johndoe/123456.jpg",
    "caption": "Exploring the mountains 🏔️ #nature #adventure"
}

// Endpoint for retrieving a specific photo
GET /photos/{photo_id}

// Endpoint for deleting a photo
DELETE /photos/{photo_id}

// Endpoint for processing a new photo
POST /images/process
{
    "image_url": "https://s3.amazonaws.com/instagram-photos/johndoe/123456.jpg"
}

// Endpoint for retrieving the processed photo
GET /images/processed/{photo_id}

// Endpoint for sending a new notification
POST /notifications
{
    "recipient_id": 123456,
    "message": "John Doe just liked your photo!"
}

// Endpoint for retrieving a list of notifications
GET /notifications?user_id=123456

// Endpoint for marking a notification as read
PATCH /notifications/{notification_id}
{
    "read": true
}

import requests

# Set up authentication
api_key = 'your_api_key'
api_secret = 'your_api_secret'
access_token = 'your_access_token'
auth = (api_key, api_secret)

# Set up request parameters
url = 'https://api.instagram.com/v1/media/upload/'
image_path = '/path/to/image.jpg'
caption = 'Check out my cool photo!'

# Upload the image
files = {'photo': open(image_path, 'rb')}
response = requests.post(url, files=files, auth=auth)

# Get the media ID from the response
media_id = response.json()['media_id']

# Use the media ID to create a post
url = 'https://api.instagram.com/v1/media/'
data = {'access_token': access_token, 'media_id': media_id, 'caption': caption}
response = requests.post(url, data=data)

import requests

# Set up authentication
api_key = 'your_api_key'
api_secret = 'your_api_secret'
access_token = 'your_access_token'
auth = (api_key, api_secret)

# Set up request parameters
url = 'https://api.instagram.com/v1/users/{user-id}/follows/'
user_id = '123456'

# Follow the user
data = {'access_token': access_token}
response = requests.post(url.format(user_id=user_id), data=data, auth=auth)

from instagram_private_api import Client, ClientCompatPatch

# Set up authentication
username = 'your_username'
password = 'your_password'
api = Client(username, password)
api.login()

# Set up request parameters
user_id = '123456'
text = 'Hey, how are you?'

# Send the DM
api.direct_message(user_id, text)

# Install instabot library using pip: pip install instabot

from instabot import Bot

# Create a new bot instance
bot = Bot()

# Login to Instagram
username = "your_username"
password = "your_password"
bot.login(username=username, password=password)

# Upload a post and set its visibility
post_path = "path/to/post.jpg"
caption = "This is my post!"
is_private = True   # Set to True for a private post and False for a public post
bot.upload_photo(photo=post_path, caption=caption, is_private=is_private)

# Logout from Instagram
bot.logout()

# Install instabot library using pip: pip install instabot

from instabot import Bot

# Create a new bot instance
bot = Bot()

# Login to Instagram
username = "your_username"
password = "your_password"
bot.login(username=username, password=password)

# Upload a story
story_path = "path/to/story.jpg"
bot.upload_story_photo(story_path)

# Logout from Instagram
bot.logout()

# Install instabot library using pip: pip install instabot

from instabot import Bot

# Create a new bot instance
bot = Bot()

# Login to Instagram
username = "your_username"
password = "your_password"
bot.login(username=username, password=password)

# Upload a post and tag a user and a location
post_path = "path/to/post.jpg"
caption = "Check out this place @user and @location"
user_id = bot.get_user_id_from_username("user")
location_id = bot.search_location("location")[0].get("location_id")
bot.upload_photo(photo=post_path, caption=caption, user_tags=[{"user_id": user_id}, {"location_id": location_id}])

# Logout from Instagram
bot.logout()

# Install instaloader library using pip: pip install instaloader

import instaloader

# Create a new Instaloader instance
L = instaloader.Instaloader()

# Login to Instagram (optional)
username = "your_username"
password = "your_password"
L.context.log("Logging in...")
L.interactive_login(username=username, password=password)

# Get a user's profile
user = instaloader.Profile.from_username(L.context, "username")

# Print the user's latest feed posts
for post in user.get_feed_posts():
    print(post)

# Logout from Instagram (optional)
L.context.log("Logging out...")
L.close()

from flask import Flask, request, jsonify, make_response

app = Flask(__name__)

# Dummy user data for demonstration
users = [
    {"id": 1, "username": "john", "password": "password1"},
    {"id": 2, "username": "jane", "password": "password2"}
]

@app.route("/login", methods=["POST"])
def login():
    username = request.json.get("username")
    password = request.json.get("password")

    # Find user by username
    user = next((user for user in users if user["username"] == username), None)

    if user and user["password"] == password:
        # Generate and return authentication token
        token = generate_auth_token(user["id"])
        return jsonify({"token": token})

    # Unauthorized access
    return make_response("Invalid username or password", 401)

# Dummy token generation for demonstration
def generate_auth_token(user_id):
    # Implement token generation logic here
    return "dummy_token"

if __name__ == "__main__":
    app.run()

from flask import Flask, request, jsonify, make_response

app = Flask(__name__)

# Dummy user data for demonstration
users = []

@app.route("/register", methods=["POST"])
def register():
    username = request.json.get("username")
    password = request.json.get("password")

    # Check if username is already taken
    if any(user["username"] == username for user in users):
        return make_response("Username already exists", 409)

    # Create a new user
    user = {"username": username, "password": password}
    users.append(user)

    return jsonify({"message": "User registered successfully"})

if __name__ == "__main__":
    app.run()

from flask import Flask, request, jsonify, make_response

app = Flask(__name__)

# Dummy user data for demonstration
users = [
    {"id": 1, "username": "john", "bio": "Hello, I'm John"}
]

@app.route("/profile/<int:user_id>", methods=["GET", "PUT"])
def profile(user_id):
    if request.method == "GET":
        # Get user profile
        user = next((user for user in users if user["id"] == user_id), None)
        if user:
            return jsonify(user)
        return make_response("User not found", 404)

    elif request.method == "PUT":
        # Update user profile
        user = next((user for user in users if user["id"] == user_id), None)
        if user:
            user["bio"] = request.json.get("bio")
            return jsonify({"message": "Profile updated successfully"})
        return make_response("User not found", 404)

if __name__ == "__main__":
    app.run()

import bcrypt

# Hash and store user password during registration
def register(username, password):
    hashed_password = bcrypt.hashpw(password.encode(), bcrypt.gensalt())
    # Store hashed_password in the database

# Validate user password during login
def login(username, password):
    # Retrieve hashed_password from the database based on the username
    hashed_password = "retrieve hashed password from database"
    if bcrypt.checkpw(password.encode(), hashed_password):
        # Passwords match, allow login
        return True
    else:
        # Passwords don't match, deny login
        return False

import boto3
from botocore.exceptions import NoCredentialsError
from flask import Flask, request, jsonify

app = Flask(__name__)

# Configure Amazon S3 credentials
AWS_ACCESS_KEY = "your-access-key"
AWS_SECRET_KEY = "your-secret-key"
BUCKET_NAME = "your-bucket-name"

s3 = boto3.client("s3", aws_access_key_id=AWS_ACCESS_KEY, aws_secret_access_key=AWS_SECRET_KEY)

@app.route("/upload", methods=["POST"])
def upload_file():
    if "file" not in request.files:
        return jsonify({"message": "No file uploaded"})

    file = request.files["file"]

    try:
        # Upload file to Amazon S3
        s3.upload_fileobj(file, BUCKET_NAME, file.filename)
        return jsonify({"message": "File uploaded successfully"})
    except NoCredentialsError:
        return jsonify({"message": "Amazon S3 credentials not found"})

if __name__ == "__main__":
    app.run()

from flask import Flask, request, jsonify, make_response

app = Flask(__name__)

# Dummy post data for demonstration
posts = [
    {"id": 1, "caption": "Beautiful sunset", "tags": ["sunset", "nature"]}
]

@app.route("/post/<int:post_id>", methods=["GET", "PUT"])
def post(post_id):
    if request.method == "GET":
        # Get post details
        post = next((post for post in posts if post["id"] == post_id), None)
        if post:
            return jsonify(post)
        return make_response("Post not found", 404)

    elif request.method == "PUT":
        # Update post caption and tags
        post = next((post for post in posts if post["id"] == post_id), None)
        if post:
            post["caption"] = request.json.get("caption")
            post["tags"] = request.json.get("tags")
            return jsonify({"message": "Post updated successfully"})
        return make_response("Post not found", 404)

if __name__ == "__main__":
    app.run()

from flask import Flask, request, jsonify, make_response

app = Flask(__name__)

# Dummy post data for demonstration
posts = [
    {"id": 1, "caption": "Beautiful sunset", "likes": 10, "comments": 3}
]

@app.route("/post/<int:post_id>/like", methods=["POST"])
def like_post(post_id):
    post = next((post for post in posts if post["id"] == post_id), None)
    if post:
        post["likes"] += 1
        return jsonify({"message": "Post liked successfully"})
    return make_response("Post not found", 404)

@app.route("/post/<int:post_id>/comment", methods=["POST"])
def add_comment(post_id):
    comment = request.json.get("comment")
    post = next((post for post in posts if post["id"] == post_id), None)
    if post:
        post["comments"].append(comment)
        return jsonify({"message": "Comment added successfully"})
    return make_response("Post not found", 404)

if __name__ == "__main__":
    app.run()

from PIL import Image

def resize_image(image_path, width, height):
    image = Image.open(image_path)
    resized_image = image.resize((width, height))
    resized_image.save("resized_image.jpg")

# Example usage
resize_image("original_image.jpg", 800, 600)

import boto3

def get_file_from_s3(bucket_name, file_key, local_file_path):
    s3 = boto3.client("s3")
    s3.download_file(bucket_name, file_key, local_file_path)

# Example usage
get_file_from_s3("your-bucket-name", "file.jpg", "local_file.jpg")

def generate_personalized_feed(user_id):
    # Retrieve user preferences from the database
    user_preferences = get_user_preferences(user_id)

    # Query and filter posts based on user preferences
    personalized_posts = query_posts_with_preferences(user_preferences)

    return personalized_posts

def sort_posts_by_popularity(posts):
    # Sort posts based on popularity metrics (e.g., likes, comments)
    sorted_posts = sorted(posts, key=lambda post: post['likes'] + post['comments'], reverse=True)
    return sorted_posts

def update_user_preferences(user_id, preferences):
    # Update user preferences in the database
    user = get_user(user_id)
    user['preferences'] = preferences
    save_user(user)

def calculate_engagement_score(post):
    # Calculate engagement score based on post likes, comments, and other relevant metrics
    engagement_score = post['likes'] + post['comments']
    return engagement_score

def follow_user(user_id, target_user_id):
    # Add target_user_id to the list of followed users for user_id
    user = get_user(user_id)
    user['following'].append(target_user_id)
    save_user(user)

def get_followers(user_id):
    # Retrieve followers for a given user_id from the database
    user = get_user(user_id)
    followers = user['followers']
    return followers

def add_comment(post_id, user_id, comment_text):
    # Create a new comment
    comment = {'user_id': user_id, 'text': comment_text}

    # Add comment to the post in the database
    post = get_post(post_id)
    post['comments'].append(comment)
    save_post(post)

def send_direct_message(sender_id, receiver_id, message_text):
    # Create a new message
    message = {'sender_id': sender_id, 'receiver_id': receiver_id, 'text': message_text}

    # Store the message in the database
    save_message(message)

def send_notification(user_id, message):
    # Create a new notification
    notification = {'user_id': user_id, 'message': message}

    # Store the notification in the database
    save_notification(notification)

def get_trending_posts():
    # Query and retrieve trending posts from the database
    trending_posts = query_trending_posts()
    return trending_posts

from elasticsearch import Elasticsearch

# Connect to Elasticsearch
es = Elasticsearch()

def search_posts(query):
    # Perform a search query on Elasticsearch
    result = es.search(index='posts', body={'query': {'match': {'caption': query}}})
    return result['hits']['hits']

def search_posts_by_hashtag(hashtag):
    # Query and retrieve posts based on the specified hashtag
    hashtagged_posts = query_posts_by_hashtag(hashtag)
    return hashtagged_posts

def get_popular_posts():
    # Query and retrieve popular posts based on engagement metrics
    popular_posts = query_popular_posts()
    return popular_posts

def generate_content_recommendations(user_id):
    # Retrieve user preferences and behavior from the database
    user_preferences = get_user_preferences(user_id)
    user_behavior = get_user_behavior(user_id)

    # Use machine learning models or recommendation algorithms to generate recommendations
    recommendations = generate_recommendations(user_preferences, user_behavior)
    return recommendations

def update_privacy_settings(user_id, privacy_preferences):
    # Update user's privacy settings in the database
    user = get_user(user_id)
    user['privacy_settings'] = privacy_preferences
    save_user(user)

def set_post_visibility(post_id, visibility):
    # Update the visibility of the post in the database
    post = get_post(post_id)
    post['visibility'] = visibility
    save_post(post)

def report_post(post_id, user_id, report_reason):
    # Create a report entry in the database
    report = {'post_id': post_id, 'user_id': user_id, 'reason': report_reason}
    save_report(report)

from cryptography.fernet import Fernet

def encrypt_password(password):
    # Generate encryption key
    key = Fernet.generate_key()

    # Create encryption cipher
    cipher = Fernet(key)

    # Encrypt password
    encrypted_password = cipher.encrypt(password.encode())

    return encrypted_password, key

# Configure load balancer settings
load_balancer = configure_load_balancer()

# Route incoming requests to backend servers
def handle_request(request):
    backend_server = load_balancer.route_request(request)
    response = backend_server.process_request(request)
    return response

import redis

# Connect to Redis cache
cache = redis.Redis(host='localhost', port=6379)

# Retrieve data from cache or database
def get_data(key):
    if cache.exists(key):
        return cache.get(key)
    else:
        data = query_data_from_database(key)
        cache.set(key, data)
        return data

# Create an index on the 'username' column for faster lookup
db.create_index('users', 'username')

# Retrieve user by username using the index
def get_user_by_username(username):
    user = db.query('users', {'username': username}, use_index=True)
    return user

from pymongo import MongoClient

# Connect to MongoDB
client = MongoClient('mongodb://localhost:27017/')

# Insert user profile into 'users' collection
def create_user_profile(profile):
    db = client['instagram']
    users_collection = db['users']
    users_collection.insert_one(profile)

import psycopg2

# Connect to PostgreSQL database
conn = psycopg2.connect(host='localhost', dbname='instagram', user='user', password='password')

# Query posts from the 'posts' table
def get_posts():
    cur = conn.cursor()
    cur.execute('SELECT * FROM posts')
    posts = cur.fetchall()
    cur.close()
    return posts

import boto3

# Create an S3 client
s3 = boto3.client('s3')

def upload_photo(photo, bucket_name, file_name):
    # Upload the photo to the specified S3 bucket
    s3.upload_fileobj(photo, bucket_name, file_name)
    
def get_photo_url(bucket_name, file_name):
    # Generate a pre-signed URL for the photo in S3
    url = s3.generate_presigned_url('get_object', Params={'Bucket': bucket_name, 'Key': file_name})
    return url

def save_user(user):
    user_id = user['id']
    shard_id = calculate_shard_id(user_id)
    shard = get_shard_connection(shard_id)
    shard.save_user(user)

def get_user(user_id):
    shard_id = calculate_shard_id(user_id)
    shard = get_shard_connection(shard_id)
    return shard.get_user(user_id)

class User:
    def __init__(self, user_id, username, password):
        self.user_id = user_id
        self.username = username
        self.password = password
        # Other user attributes
    
class Stock:
    def __init__(self, stock_id, symbol, name, current_price):
        self.stock_id = stock_id
        self.symbol = symbol
        self.name = name
        self.current_price = current_price
        # Other stock attributes

class Order:
    def __init__(self, order_id, user, stock, order_type, quantity):
        self.order_id = order_id
        self.user = user
        self.stock = stock
        self.order_type = order_type
        self.quantity = quantity
        # Other order attributes

class Transaction:
    def __init__(self, transaction_id, order, price, quantity):
        self.transaction_id = transaction_id
        self.order = order
        self.price = price
        self.quantity = quantity
        # Other transaction attributes

class Robinhood:
    def __init__(self):
        self.users = []
        self.stocks = []
        self.orders = []
        self.transactions = []

    def add_user(self, user):
        self.users.append(user)
    
    def add_stock(self, stock):
        self.stocks.append(stock)
    
    def place_order(self, order):
        self.orders.append(order)
    
    def execute_transaction(self, transaction):
        self.transactions.append(transaction)

    # Other methods for managing users, stocks, orders, transactions, etc.

from flask import Flask, request, jsonify

app = Flask(__name__)

# Endpoint for user registration
@app.route('/register', methods=['POST'])
def register_user():
    # Retrieve user data from the request body
    data = request.json
    # Perform user registration logic
    # ...
    return jsonify({'message': 'User registered successfully'})

# Endpoint for user login
@app.route('/login', methods=['POST'])
def login_user():
    # Retrieve user credentials from the request body
    data = request.json
    # Perform user authentication logic
    # ...
    return jsonify({'message': 'User logged in successfully'})

# Endpoint for retrieving stock information
@app.route('/stocks/<symbol>', methods=['GET'])
def get_stock_info(symbol):
    # Retrieve stock information based on the symbol
    # ...
    return jsonify(stock_info)

# Endpoint for placing a buy order
@app.route('/orders/buy', methods=['POST'])
def place_buy_order():
    # Retrieve order data from the request body
    data = request.json
    # Perform buy order placement logic
    # ...
    return jsonify({'message': 'Buy order placed successfully'})

# Endpoint for placing a sell order
@app.route('/orders/sell', methods=['POST'])
def place_sell_order():
    # Retrieve order data from the request body
    data = request.json
    # Perform sell order placement logic
    # ...
    return jsonify({'message': 'Sell order placed successfully'})

# Endpoint for retrieving user account balance
@app.route('/account/balance', methods=['GET'])
def get_account_balance():
    # Retrieve user account balance
    # ...
    return jsonify(account_balance)

if __name__ == '__main__':
    app.run()

from flask import Flask, request, jsonify

app = Flask(__name__)

# User service
@app.route('/users/register', methods=['POST'])
def register_user():
    # User registration logic
    # ...
    return jsonify({'message': 'User registered successfully'})

@app.route('/users/login', methods=['POST'])
def login_user():
    # User login logic
    # ...
    return jsonify({'message': 'User logged in successfully'})

# Stock service
@app.route('/stocks/<symbol>', methods=['GET'])
def get_stock_info(symbol):
    # Stock information retrieval logic
    # ...
    return jsonify(stock_info)

# Trading service
@app.route('/orders/buy', methods=['POST'])
def place_buy_order():
    # Buy order placement logic
    # ...
    return jsonify({'message': 'Buy order placed successfully'})

@app.route('/orders/sell', methods=['POST'])
def place_sell_order():
    # Sell order placement logic
    # ...
    return jsonify({'message': 'Sell order placed successfully'})

# Account service
@app.route('/account/balance', methods=['GET'])
def get_account_balance():
    # Account balance retrieval logic
    # ...
    return jsonify(account_balance)

if __name__ == '__main__':
    app.run()

class Robinhood:
    def __init__(self):
        self.users = []
        self.stocks = []
        self.market_data = {}

    def register_user(self, username, password):
        user = {'username': username, 'password': password, 'balance': 0, 'portfolio': {}}
        self.users.append(user)
        return user

    def login_user(self, username, password):
        for user in self.users:
            if user['username'] == username and user['password'] == password:
                return user
        return None

    def buy_stock(self, user, stock_symbol, quantity):
        stock = self._get_stock(stock_symbol)
        if stock is None:
            return "Stock not found"
        stock_price = stock['price']
        total_cost = stock_price * quantity

        if user['balance'] < total_cost:
            return "Insufficient funds"

        fractional_shares = quantity % 1
        if fractional_shares > 0:
            self._update_portfolio(user, stock_symbol, quantity - fractional_shares)
        else:
            self._update_portfolio(user, stock_symbol, quantity)

        user['balance'] -= total_cost
        return "Stock purchased successfully"

    def sell_stock(self, user, stock_symbol, quantity):
        stock = self._get_stock(stock_symbol)
        if stock is None:
            return "Stock not found"
        stock_price = stock['price']

        if stock_symbol not in user['portfolio'] or user['portfolio'][stock_symbol] < quantity:
            return "Insufficient shares"

        total_cost = stock_price * quantity
        user['balance'] += total_cost
        self._update_portfolio(user, stock_symbol, -quantity)
        return "Stock sold successfully"

    def add_stock(self, stock_symbol, price):
        stock = {'symbol': stock_symbol, 'price': price}
        self.stocks.append(stock)

    def update_stock_price(self, stock_symbol, price):
        stock = self._get_stock(stock_symbol)
        if stock is not None:
            stock['price'] = price

    def _get_stock(self, stock_symbol):
        for stock in self.stocks:
            if stock['symbol'] == stock_symbol:
                return stock
        return None

    def _update_portfolio(self, user, stock_symbol, quantity):
        if stock_symbol in user['portfolio']:
            user['portfolio'][stock_symbol] += quantity
        else:
            user['portfolio'][stock_symbol] = quantity


# Example usage
robinhood = Robinhood()

# Register a user
user = robinhood.register_user('john123', 'password123')

# Login
user = robinhood.login_user('john123', 'password123')

# Add stocks
robinhood.add_stock('AAPL', 150.25)
robinhood.add_stock('GOOGL', 2500.00)

# Buy stocks
robinhood.buy_stock(user, 'AAPL', 5)
robinhood.buy_stock(user, 'GOOGL', 2.5)

# Sell stocks
robinhood.sell_stock(user, 'AAPL', 2)
robinhood.sell_stock(user, 'GOOGL', 1.5)

# Update stock price
robinhood.update_stock_price('AAPL', 160.75)

from flask import Flask, request, jsonify

app = Flask(__name__)

users = []
stocks = []
orders = []
transactions = []

# User Registration API
@app.route('/users/register', methods=['POST'])
def register_user():
    data = request.get_json()
    username = data['username']
    email = data['email']
    password = data['password']
    user_id = len(users) + 1

    user = {
        'user_id': user_id,
        'username': username,
        'email': email,
        'password': password
    }

    users.append(user)

    return jsonify({'message': 'User registered successfully'})

# User Login API
@app.route('/users/login', methods=['POST'])
def login_user():
    data = request.get_json()
    username = data['username']
    password = data['password']

    for user in users:
        if user['username'] == username and user['password'] == password:
            return jsonify({'message': 'Login successful'})

    return jsonify({'message': 'Invalid credentials'}), 401

# Stock Information API
@app.route('/stocks/<symbol>', methods=['GET'])
def get_stock(symbol):
    for stock in stocks:
        if stock['symbol'] == symbol:
            return jsonify(stock)

    return jsonify({'message': 'Stock not found'}), 404

# Place Order API
@app.route('/orders', methods=['POST'])
def place_order():
    data = request.get_json()
    user_id = data['user_id']
    stock_id = data['stock_id']
    order_type = data['order_type']
    quantity = data['quantity']
    order_id = len(orders) + 1

    order = {
        'order_id': order_id,
        'user_id': user_id,
        'stock_id': stock_id,
        'order_type': order_type,
        'quantity': quantity
    }

    orders.append(order)

    return jsonify({'message': 'Order placed successfully'})

# Execute Transaction API
@app.route('/transactions', methods=['POST'])
def execute_transaction():
    data = request.get_json()
    order_id = data['order_id']
    price = data['price']
    quantity = data['quantity']
    transaction_id = len(transactions) + 1

    transaction = {
        'transaction_id': transaction_id,
        'order_id': order_id,
        'price': price,
        'quantity': quantity
    }

    transactions.append(transaction)

    return jsonify({'message': 'Transaction executed successfully'})

if __name__ == '__main__':
    app.run()

from flask import Flask, jsonify, request

app = Flask(__name__)

# User Service
@app.route('/api/users/register', methods=['POST'])
def register_user():
    user_data = request.get_json()
    
    # Logic to create a new user in the database
    # Example logic: Save user data in the database
    user_id = save_user_to_database(user_data)
    
    return jsonify({'message': 'User registered successfully', 'user_id': user_id})

@app.route('/api/users/login', methods=['POST'])
def login_user():
    login_data = request.get_json()
    username = login_data['username']
    password = login_data['password']
    
    # Logic to verify user credentials and generate authentication token
    # Example logic: Check if the username and password match
    if username == 'example_user' and password == 'example_password':
        token = generate_auth_token()
        return jsonify({'message': 'User logged in successfully', 'token': token})
    else:
        return jsonify({'message': 'Invalid credentials'})

# Restaurant Service
@app.route('/api/restaurants', methods=['GET'])
def get_restaurants():
    # Logic to fetch a list of restaurants from the database
    restaurants = fetch_restaurants_from_database()
    return jsonify({'message': 'List of restaurants', 'restaurants': restaurants})

@app.route('/api/restaurants/<int:restaurant_id>', methods=['GET'])
def get_restaurant(restaurant_id):
    # Logic to fetch the details of the specified restaurant from the database
    restaurant = fetch_restaurant_from_database(restaurant_id)
    if restaurant:
        return jsonify({'message': 'Restaurant details', 'restaurant': restaurant})
    else:
        return jsonify({'message': 'Restaurant not found'})

# Order Service
@app.route('/api/orders', methods=['POST'])
def place_order():
    order_data = request.get_json()
    
    # Logic to create a new order in the database
    order_id = create_order_in_database(order_data)
    
    return jsonify({'message': 'Order placed successfully', 'order_id': order_id})

@app.route('/api/orders/<int:order_id>', methods=['GET'])
def get_order(order_id):
    # Logic to fetch the details of the specified order from the database
    order = fetch_order_from_database(order_id)
    if order:
        return jsonify({'message': 'Order details', 'order': order})
    else:
        return jsonify({'message': 'Order not found'})

@app.route('/api/orders/<int:order_id>', methods=['PUT'])
def update_order(order_id):
    order_data = request.get_json()
    
    # Logic to update the details of the specified order in the database
    update_order_in_database(order_id, order_data)
    
    return jsonify({'message': 'Order updated successfully'})

@app.route('/api/orders/<int:order_id>', methods=['DELETE'])
def cancel_order(order_id):
    # Logic to cancel the specified order in the database
    cancel_order_in_database(order_id)
    
    return jsonify({'message': 'Order canceled successfully'})

# Payment Service
@app.route('/api/payments', methods=['POST'])
def initiate_payment():
    payment_data = request.get_json()
    
    # Logic to initiate a payment for the order
    payment_id = initiate_payment_for_order(payment_data)
    
    return jsonify({'message': 'Payment initiated', 'payment_id': payment_id})

@app.route('/api/payments/<int:payment_id>', methods=['GET'])
def get_payment(payment_id):
    # Logic to fetch the details of the specified payment from the database
    payment = fetch_payment_from_database(payment_id)
    if payment:
        return jsonify({'message': 'Payment details', 'payment': payment})
    else:
        return jsonify({'message': 'Payment not found'})

# Review Service
@app.route('/api/restaurants/<int:restaurant_id>/reviews', methods=['POST'])
def submit_review(restaurant_id):
    review_data = request.get_json()
    
    # Logic to create a new review for the specified restaurant in the database
    review_id = create_review_for_restaurant(review_data, restaurant_id)
    
    return jsonify({'message': 'Review submitted', 'review_id': review_id})

@app.route('/api/restaurants/<int:restaurant_id>/reviews', methods=['GET'])
def get_reviews(restaurant_id):
    # Logic to fetch the reviews of the specified restaurant from the database
    reviews = fetch_reviews_for_restaurant(restaurant_id)
    return jsonify({'message': 'Restaurant reviews', 'reviews': reviews})

# Placeholder functions for database operations, replace with your actual implementation
def save_user_to_database(user_data):
    # Save user data to the database and return the user ID
    # ...
    return 1

def generate_auth_token():
    # Generate an authentication token for the user
    # ...
    return 'example_token'

def fetch_restaurants_from_database():
    # Fetch a list of restaurants from the database
    # ...
    return []

def fetch_restaurant_from_database(restaurant_id):
    # Fetch the details of the specified restaurant from the database
    # ...
    return None

def create_order_in_database(order_data):
    # Create a new order in the database and return the order ID
    # ...
    return 1

def fetch_order_from_database(order_id):
    # Fetch the details of the specified order from the database
    # ...
    return None

def update_order_in_database(order_id, order_data):
    # Update the details of the specified order in the database
    # ...
    pass

def cancel_order_in_database(order_id):
    # Cancel the specified order in the database
    # ...
    pass

def initiate_payment_for_order(payment_data):
    # Initiate a payment for the order and return the payment ID
    # ...
    return 1

def fetch_payment_from_database(payment_id):
    # Fetch the details of the specified payment from the database
    # ...
    return None

def create_review_for_restaurant(review_data, restaurant_id):
    # Create a new review for the specified restaurant in the database and return the review ID
    # ...
    return 1

def fetch_reviews_for_restaurant(restaurant_id):
    # Fetch the reviews of the specified restaurant from the database
    # ...
    return []

if __name__ == '__main__':
    app.run()

from flask import Flask, jsonify, request

app = Flask(__name__)

# User class
class User:
    def __init__(self, user_id, name, address):
        self.user_id = user_id
        self.name = name
        self.address = address
        self.order_history = []

# Restaurant class
class Restaurant:
    def __init__(self, restaurant_id, name, menu, ratings):
        self.restaurant_id = restaurant_id
        self.name = name
        self.menu = menu
        self.ratings = ratings

# Order class
class Order:
    def __init__(self, order_id, user_id, restaurant_id, items):
        self.order_id = order_id
        self.user_id = user_id
        self.restaurant_id = restaurant_id
        self.items = items
        self.status = 'Placed'

# Sample data for demonstration
users = {
    'user1': User('user1', 'John Doe', '123 Main St'),
    'user2': User('user2', 'Jane Smith', '456 Elm St')
}

restaurants = {
    'restaurant1': Restaurant('restaurant1', 'Pizza Place', ['Margherita', 'Pepperoni'], 4.5),
    'restaurant2': Restaurant('restaurant2', 'Burger Joint', ['Cheeseburger', 'Veggie Burger'], 4.2)
}

orders = {}

# User API
@app.route('/api/users/register', methods=['POST'])
def register_user():
    data = request.get_json()
    user_id = data['user_id']
    name = data['name']
    address = data['address']
    users[user_id] = User(user_id, name, address)
    return jsonify({'message': 'User registered successfully'})

@app.route('/api/users/login', methods=['POST'])
def login_user():
    data = request.get_json()
    user_id = data['user_id']
    if user_id in users:
        return jsonify({'message': 'User logged in successfully'})
    else:
        return jsonify({'message': 'User not found'})

@app.route('/api/users/<user_id>/profile', methods=['GET'])
def get_user_profile(user_id):
    if user_id in users:
        user = users[user_id]
        return jsonify({'user_id': user.user_id, 'name': user.name, 'address': user.address})
    else:
        return jsonify({'message': 'User not found'})

# Restaurant API
@app.route('/api/restaurants', methods=['GET'])
def get_restaurants():
    restaurant_list = []
    for restaurant in restaurants.values():
        restaurant_list.append({'restaurant_id': restaurant.restaurant_id, 'name': restaurant.name})
    return jsonify({'restaurants': restaurant_list})

@app.route('/api/restaurants/<restaurant_id>', methods=['GET'])
def get_restaurant(restaurant_id):
    if restaurant_id in restaurants:
        restaurant = restaurants[restaurant_id]
        return jsonify({'restaurant_id': restaurant.restaurant_id, 'name': restaurant.name, 'menu': restaurant.menu, 'ratings': restaurant.ratings})
    else:
        return jsonify({'message': 'Restaurant not found'})

# Order API
@app.route('/api/orders', methods=['POST'])
def place_order():
    data = request.get_json()
    order_id = data['order_id']
    user_id = data['user_id']
    restaurant_id = data['restaurant_id']
    items = data['items']
    order = Order(order_id, user_id, restaurant_id, items)
    orders[order_id] = order
    user = users[user_id]
    user.order_history.append(order)
    return jsonify({'message': 'Order placed successfully'})

@app.route('/api/orders/<order_id>', methods=['GET'])
def get_order(order_id):
    if order_id in orders:
        order = orders[order_id]
        return jsonify({'order_id': order.order_id, 'user_id': order.user_id, 'restaurant_id': order.restaurant_id, 'items': order.items, 'status': order.status})
    else:
        return jsonify({'message': 'Order not found'})

@app.route('/api/orders/<order_id>', methods=['PUT'])
def update_order(order_id):
    if order_id in orders:
        data = request.get_json()
        status = data['status']
        order = orders[order_id]
        order.status = status
        return jsonify({'message': 'Order updated successfully'})
    else:
        return jsonify({'message': 'Order not found'})

if __name__ == '__main__':
    app.run()

from flask import Flask, request, jsonify

app = Flask(__name__)

users = []  # List to store registered users

# Endpoint to register a new user
@app.route('/api/users/register', methods=['POST'])
def register_user():
    data = request.json
    email = data['email']
    password = data['password']

    # Check if the user already exists
    for user in users:
        if user['email'] == email:
            return jsonify({'message': 'User already exists'})

    # Create a new user
    new_user = {
        'email': email,
        'password': password
    }

    # Add the new user to the list
    users.append(new_user)

    return jsonify({'message': 'User registered successfully'})

# Endpoint to authenticate and log in a user
@app.route('/api/users/login', methods=['POST'])
def login_user():
    data = request.json
    email = data['email']
    password = data['password']

    # Find the user in the list
    for user in users:
        if user['email'] == email and user['password'] == password:
            return jsonify({'message': 'User logged in successfully'})

    return jsonify({'message': 'Invalid credentials'})

if __name__ == '__main__':
    app.run()

from flask import Flask, jsonify

app = Flask(__name__)

restaurants = [
    {
        'id': 1,
        'name': 'Restaurant 1',
        'cuisine': 'Italian'
    },
    {
        'id': 2,
        'name': 'Restaurant 2',
        'cuisine': 'Indian'
    }
]

# Endpoint to get a list of available restaurants
@app.route('/api/restaurants', methods=['GET'])
def get_restaurants():
    return jsonify(restaurants)

# Endpoint to get details of a specific restaurant
@app.route('/api/restaurants/<int:restaurant_id>', methods=['GET'])
def get_restaurant(restaurant_id):
    for restaurant in restaurants:
        if restaurant['id'] == restaurant_id:
            return jsonify(restaurant)

    return jsonify({'message': 'Restaurant not found'})

if __name__ == '__main__':
    app.run()

from flask import Flask, request, jsonify

app = Flask(__name__)

menus = {
    1: {
        'id': 1,
        'name': 'Restaurant 1',
        'menu': ['Pizza', 'Pasta', 'Salad']
    },
    2: {
        'id': 2,
        'name': 'Restaurant 2',
        'menu': ['Biryani', 'Curry', 'Naan']
    }
}

orders = []

# Endpoint to get the menu of a restaurant
@app.route('/api/restaurants/<int:restaurant_id>/menu', methods=['GET'])
def get_menu(restaurant_id):
    if restaurant_id in menus:
        return jsonify(menus[restaurant_id]['menu'])

    return jsonify({'message': 'Menu not found'})

# Endpoint to place a new order
@app.route('/api/orders', methods=['POST'])
def place_order():
    data = request.json
    restaurant_id = data['restaurant_id']
    items = data['items']

    # Check if the restaurant exists
    if restaurant_id not in menus:
        return jsonify({'message': 'Restaurant not found'})

    # Create a new order
    new_order = {
        'restaurant_id': restaurant_id,
        'items': items
    }

    # Add the new order to the list
    orders.append(new_order)

    return jsonify({'message': 'Order placed successfully'})

# Endpoint to get details of a specific order
@app.route('/api/orders/<int:order_id>', methods=['GET'])
def get_order(order_id):
    for order in orders:
        if order['id'] == order_id:
            return jsonify(order)

    return jsonify({'message': 'Order not found'})

# Endpoint to update an existing order
@app.route('/api/orders/<int:order_id>', methods=['PUT'])
def update_order(order_id):
    data = request.json
    items = data['items']

    for order in orders:
        if order['id'] == order_id:
            order['items'] = items
            return jsonify({'message': 'Order updated successfully'})

    return jsonify({'message': 'Order not found'})

# Endpoint to cancel an order
@app.route('/api/orders/<int:order_id>', methods=['DELETE'])
def cancel_order(order_id):
    for order in orders:
        if order['id'] == order_id:
            orders.remove(order)
            return jsonify({'message': 'Order canceled successfully'})

    return jsonify({'message': 'Order not found'})

if __name__ == '__main__':
    app.run()

from flask import Flask, jsonify, request

app = Flask(__name__)

# User Registration and Authentication
@app.route('/api/users/register', methods=['POST'])
def register_user():
    # Code for user registration
    user_data = request.get_json()
    # Extract user registration data from the request
    username = user_data.get('username')
    email = user_data.get('email')
    password = user_data.get('password')

    # Perform user registration logic (e.g., create a new user in the database)
    # ...

    return jsonify({'message': 'User registered successfully'})

@app.route('/api/users/login', methods=['POST'])
def login_user():
    # Code for user login
    login_data = request.get_json()
    # Extract user login data from the request
    username = login_data.get('username')
    password = login_data.get('password')

    # Perform user login logic (e.g., verify user credentials)
    # ...

    return jsonify({'message': 'User logged in successfully'})

# Restaurant Listing and Search
@app.route('/api/restaurants', methods=['GET'])
def get_restaurants():
    # Code to retrieve restaurants
    # ...

@app.route('/api/restaurants/<restaurant_id>', methods=['GET'])
def get_restaurant(restaurant_id):
    # Code to retrieve a specific restaurant
    # ...

# Menu and Order Management
@app.route('/api/restaurants/<restaurant_id>/menu', methods=['GET'])
def get_menu(restaurant_id):
    # Code to retrieve the menu of a restaurant
    # ...

@app.route('/api/orders', methods=['POST'])
def place_order():
    # Code to place a new order
    order_data = request.get_json()
    # Extract order data from the request
    # ...

    # Perform order placement logic (e.g., create a new order in the database)
    # ...

    return jsonify({'message': 'Order placed successfully'})

@app.route('/api/orders/<order_id>', methods=['GET'])
def get_order(order_id):
    # Code to retrieve a specific order
    # ...

@app.route('/api/orders/<order_id>', methods=['PUT'])
def update_order(order_id):
    # Code to update an existing order
    order_data = request.get_json()
    # Extract updated order data from the request
    # ...

    # Perform order update logic (e.g., update the order details in the database)
    # ...

    return jsonify({'message': 'Order updated successfully'})

# Real-Time Order Tracking
@app.route('/api/orders/<order_id>/track', methods=['GET'])
def track_order(order_id):
    # Code to track an order in real-time
    # ...

# Payment Integration
@app.route('/api/payments', methods=['POST'])
def initiate_payment():
    # Code to initiate a payment
    payment_data = request.get_json()
    # Extract payment data from the request
    # ...

    # Perform payment initiation logic (e.g., initiate the payment process)
    # ...

    return jsonify({'message': 'Payment initiated'})

@app.route('/api/payments/<payment_id>', methods=['GET'])
def get_payment(payment_id):
    # Code to retrieve a specific payment
    # ...

# Ratings and Reviews
@app.route('/api/restaurants/<restaurant_id>/reviews', methods=['POST'])
def submit_review(restaurant_id):
    # Code to submit a review for a restaurant
    review_data = request.get_json()
    # Extract review data from the request
    # ...

    # Perform review submission logic (e.g., create a new review in the database)
    # ...

    return jsonify({'message': 'Review submitted'})

@app.route('/api/restaurants/<restaurant_id>/reviews', methods=['GET'])
def get_reviews(restaurant_id):
    # Code to retrieve reviews for a specific restaurant
    # ...

if __name__ == '__main__':
    app.run()

class User:
    def __init__(self, user_id, username, password):
        self.user_id = user_id
        self.username = username
        self.password = password
        # Other user attributes
        
class Transaction:
    def __init__(self, transaction_id, sender_id, receiver_id, amount):
        self.transaction_id = transaction_id
        self.sender_id = sender_id
        self.receiver_id = receiver_id
        self.amount = amount
        # Other transaction attributes
        
class CashCard:
    def __init__(self, card_id, user_id, card_number, expiration_date):
        self.card_id = card_id
        self.user_id = user_id
        self.card_number = card_number
        self.expiration_date = expiration_date
        # Other card attributes
        
class Investment:
    def __init__(self, investment_id, user_id, stock_symbol, quantity):
        self.investment_id = investment_id
        self.user_id = user_id
        self.stock_symbol = stock_symbol
        self.quantity = quantity
        # Other investment attributes
        
class Like:
    def __init__(self, like_id, user_id, post_id):
        self.like_id = like_id
        self.user_id = user_id
        self.post_id = post_id
        # Other like attributes
        
class Comment:
    def __init__(self, comment_id, user_id, post_id, caption_text):
        self.comment_id = comment_id
        self.user_id = user_id
        self.post_id = post_id
        self.caption_text = caption_text
        # Other comment attributes
        
class Post:
    def __init__(self, post_id, user_id, photo_url, caption, timestamp, location):
        self.post_id = post_id
        self.user_id = user_id
        self.photo_url = photo_url
        self.caption = caption
        self.timestamp = timestamp
        self.location = location
        # Other post attributes
        
class CashApp:
    def __init__(self):
        self.users = {}
        self.transactions = []
        self.cash_cards = {}
        self.investments = {}
        self.likes = {}
        self.comments = {}
        self.posts = {}
        
    # Methods to add, retrieve, and update user data
    def add_user(self, user):
        self.users[user.user_id] = user
        
    def get_user_by_id(self, user_id):
        return self.users.get(user_id)
        
    # Methods to perform transactions
    def create_transaction(self, transaction):
        self.transactions.append(transaction)
        
    # Methods to manage cash cards
    def add_cash_card(self, cash_card):
        self.cash_cards[cash_card.card_id] = cash_card
        
    def get_cash_card_by_id(self, card_id):
        return self.cash_cards.get(card_id)
        
    # Methods to manage investments
    def add_investment(self, investment):
        self.investments[investment.investment_id] = investment
        
    def get_investment_by_id(self, investment_id):
        return self.investments.get(investment_id)
        
    # Methods to manage likes and comments
    def add_like(self, like):
        self.likes[like.like_id] = like
        
    def add_comment(self, comment):
        self.comments[comment.comment_id] = comment
        
    # Methods to manage posts
    def add_post(self, post):
        self.posts[post.post_id] = post

from flask import Flask, request, jsonify

app = Flask(__name__)

# User Registration API
@app.route('/api/users/register', methods=['POST'])
def register_user():
    # Handle user registration logic here
    # ...

    response = {"message": "User registered successfully"}
    return jsonify(response)

# User Login API
@app.route('/api/users/login', methods=['POST'])
def login_user():
    # Handle user login logic here
    # ...

    response = {
        "access_token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...",
        "token_type": "Bearer"
    }
    return jsonify(response)

# Create Transaction API
@app.route('/api/transactions/create', methods=['POST'])
def create_transaction():
    # Extract transaction details from the request body
    sender_id = request.json['sender_id']
    receiver_id = request.json['receiver_id']
    amount = request.json['amount']

    # Handle transaction creation logic here
    #...

    response = {"message": "Transaction created successfully"}
    return jsonify(response)

# Get Transaction API
@app.route('/api/transactions/<transaction_id>', methods=['GET'])
def get_transaction(transaction_id):
    # Handle transaction retrieval logic here
    # ...

    response = {
        "transaction_id": transaction_id,
        "sender_id": "user123",
        "receiver_id": "user456",
        "amount": 100.50,
        "timestamp": "2023-07-08T10:30:00Z",
        "status": "completed"
    }
    return jsonify(response)

if __name__ == '__main__':
    app.run()

from flask import Flask, request

app = Flask(__name__)

cash_app = CashApp()

# Endpoint for creating a new user account
@app.route("/users", methods=["POST"])
def create_user():
    data = request.get_json()
    user_id = data["user_id"]
    username = data["username"]
    password = data["password"]
    user = User(user_id, username, password)
    cash_app.add_user(user)
    return {"message": "User created successfully"}, 201

# Endpoint for retrieving user information
@app.route("/users/<user_id>", methods=["GET"])
def get_user(user_id):
    user = cash_app.get_user_by_id(user_id)
    if user:
        return {
            "user_id": user.user_id,
            "username": user.username,
            # Include other user attributes
        }, 200
    else:
        return {"message": "User not found"}, 404

# Endpoint for updating user information
@app.route("/users/<user_id>", methods=["PATCH"])
def update_user(user_id):
    data = request.get_json()
    user = cash_app.get_user_by_id(user_id)
    if user:
        # Update user attributes
        user.username = data.get("username", user.username)
        user.password = data.get("password", user.password)
        # Update other user attributes
        return {"message": "User updated successfully"}, 200
    else:
        return {"message": "User not found"}, 404

# Endpoint for deleting a user account
@app.route("/users/<user_id>", methods=["DELETE"])
def delete_user(user_id):
    user = cash_app.get_user_by_id(user_id)
    if user:
        # Delete user from the CashApp system
        del cash_app.users[user_id]
        return {"message": "User deleted successfully"}, 200
    else:
        return {"message": "User not found"}, 404

def send_money(sender, receiver, amount):
    sender_balance = get_account_balance(sender)
    receiver_balance = get_account_balance(receiver)

    if sender_balance >= amount:
        deduct_amount(sender, amount)
        increase_amount(receiver, amount)
        update_transaction_records(sender, receiver, amount, "completed")
        return "Money sent successfully"
    else:
        update_transaction_records(sender, receiver, amount, "failed")
        return "Insufficient funds"

def receive_money(sender, receiver, amount):
    increase_amount(receiver, amount)
    update_transaction_records(sender, receiver, amount, "completed")
    return "Money received successfully"

class CashCard:
    def __init__(self, card_number, expiration_date):
        self.card_number = card_number
        self.expiration_date = expiration_date

def request_cash_card(user):
    cash_card = CashCard(generate_card_number(), generate_expiration_date())
    associate_cash_card(user, cash_card)
    return cash_card

def make_purchase(cash_card, amount):
    if cash_card.balance >= amount:
        deduct_amount_from_cash_card(cash_card, amount)
        update_transaction_records(cash_card, amount, "completed")
        return "Purchase made successfully"
    else:
        update_transaction_records(cash_card, amount, "failed")
        return "Insufficient funds on the Cash Card"

class Investment:
    def __init__(self, symbol, quantity):
        self.symbol = symbol
        self.quantity = quantity

def buy_stock(user, symbol, quantity):
    stock_price = get_stock_price(symbol)
    purchase_amount = stock_price * quantity

    if user.balance >= purchase_amount:
        deduct_amount(user, purchase_amount)
        add_investment(user, Investment(symbol, quantity))
        update_transaction_records(user, purchase_amount, "completed")
        return "Stocks bought successfully"
    else:
        update_transaction_records(user, purchase_amount, "failed")
        return "Insufficient funds to buy stocks"

def sell_stock(user, symbol, quantity):
    stock_price = get_stock_price(symbol)
    sale_amount = stock_price * quantity

    if has_sufficient_stocks(user, symbol, quantity):
        decrease_stocks(user, symbol, quantity)
        increase_amount(user, sale_amount)
        update_transaction_records(user, sale_amount, "completed")
        return "Stocks sold successfully"
    else:
        update_transaction_records(user, sale_amount, "failed")
        return "Insufficient stocks to sell"

class CashBoost:
    def __init__(self, merchant, discount):
        self.merchant = merchant
        self.discount = discount

def apply_cash_boost(user, cash_card, merchant):
    cash_boost = get_cash_boost_for_merchant(merchant)

    if cash_boost:
        discount = calculate_discount(cash_boost.discount, cash_card.balance)
        discounted_amount = cash_card.balance - discount

        update_transaction_records(cash_card, discounted_amount, "completed")
        return "Cash boost applied successfully"
    else:
        update_transaction_records(cash_card, cash_card.balance, "completed")
        return "No cash boost available for this merchant"

def buy_bitcoin(user, amount):
    bitcoin_price = get_bitcoin_price()
    purchase_amount = bitcoin_price * amount

    if user.balance >= purchase_amount:
        deduct_amount(user, purchase_amount)
        increase_bitcoin_holdings(user, amount)
        update_transaction_records(user, purchase_amount, "completed")
        return "Bitcoin bought successfully"
    else:
        update_transaction_records(user, purchase_amount, "failed")
        return "Insufficient funds to buy Bitcoin"

def sell_bitcoin(user, amount):
    bitcoin_price = get_bitcoin_price()
    sale_amount = bitcoin_price * amount

    if has_sufficient_bitcoin_holdings(user, amount):
        decrease_bitcoin_holdings(user, amount)
        increase_amount(user, sale_amount)
        update_transaction_records(user, sale_amount, "completed")
        return "Bitcoin sold successfully"
    else:
        update_transaction_records(user, sale_amount, "failed")
        return "Insufficient Bitcoin holdings to sell"

class GoogleDuo:
    def __init__(self):
        # Initialize any necessary components for Google Duo
        pass

    def start_video_call(self, user_id: int, contact_id: int) -> bool:
        # Simulate the logic for starting a video call between two users
        # Your implementation for starting a video call goes here
        print(f"User {user_id} is starting a video call with user {contact_id}.")
        return True

    def end_video_call(self, user_id: int, contact_id: int) -> bool:
        # Simulate the logic for ending an ongoing video call
        # Your implementation for ending a video call goes here
        print(f"User {user_id} has ended the video call with user {contact_id}.")
        return True

if __name__ == "__main__":
    google_duo = GoogleDuo()

    # Simulate video call requests
    for i in range(800_000_000):
        user_id = i % 100_000_000  # Simulating 100 million users
        contact_id = (i + 1) % 100_000_000
        google_duo.start_video_call(user_id, contact_id)
        # Simulate video call duration (5 minutes)
        # ...

    # Simulate ending video calls
    for i in range(800_000_000):
        user_id = i % 100_000_000  # Simulating 100 million users
        contact_id = (i + 1) % 100_000_000
        google_duo.end_video_call(user_id, contact_id)
     

# Low-level API implementation

class Authentication:
    @staticmethod
    def login(username: str, password: str) -> bool:
        # Implementation for user authentication (dummy implementation)
        if username == "user" and password == "pass":
            return True
        else:
            return False

class Contacts:
    @staticmethod
    def get_contacts(user_id: int) -> List[str]:
        # Implementation for retrieving contacts (dummy implementation)
        if user_id == 12345:
            return ["Contact1", "Contact2", "Contact3"]
        else:
            return []

class CallManagement:
    @staticmethod
    def start_video_call(user_id: int, contact: str) -> bool:
        # Implementation for call initiation (dummy implementation)
        if user_id == 12345 and contact in ["Contact1", "Contact2", "Contact3"]:
            print(f"User {user_id} is calling {contact}.")
            return True
        else:
            return False

class CallStatus:
    @staticmethod
    def get_call_status(user_id: int) -> str:
        # Implementation for call status retrieval (dummy implementation)
        if user_id == 12345:
            return "Call in progress"
        else:
            return "No ongoing call"

# Example usage:

if __name__ == "__main__":
    # Sample usage of high-level API functionalities
    user_id = 12345
    username = "user"
    password = "pass"
    contact_to_call = "Contact1"

    if Authentication.login(username, password):
        print("User authentication successful.")
        contacts = Contacts.get_contacts(user_id)
        print("User's contacts:", contacts)

        if contact_to_call in contacts:
            if CallManagement.start_video_call(user_id, contact_to_call):
                print(f"Call to {contact_to_call} initiated.")
                call_status = CallStatus.get_call_status(user_id)
                print("Call status:", call_status)
            else:
                print("Failed to initiate the call.")
        else:
            print(f"{contact_to_call} is not in the user's contacts.")
    else:
        print("User authentication failed.")

from flask import Flask, request

app = Flask(__name__)
google_duo = GoogleDuo()

# User Registration and Authentication
@app.route('/users', methods=['POST'])
def registerUser():
    data = request.get_json()
    userId = data['userId']
    username = data['username']
    password = data['password']
    user = User(userId, username, password)
    google_duo.addUser(user)
    return {"message": "User registration successful"}, 201

# Get User Profile
@app.route('/users/<userId>', methods=['GET'])
def getUserProfile(userId):
    user = google_duo.getUserById(userId)
    if user:
        return {
            "userId": user.userId,
            "username": user.username,
            "followers": user.followers,
            "following": user.contacts,
            "posts": [
                {
                    "postId": post.postId,
                    "caption": post.caption,
                    "imageUrl": post.imageUrl,
                    "timestamp": post.timestamp.isoformat()
                }
                for post in user.posts
            ]
        }, 200
    else:
        return {"message": "User not found"}, 404

# Create Post
@app.route('/users/<userId>/posts', methods=['POST'])
def createPost(userId):
    user = google_duo.getUserById(userId)
    if not user:
        return {"message": "User not found"}, 404

    data = request.get_json()
    caption = data.get('caption', '')
    imageUrl = data.get('imageUrl', '')
    timestamp = datetime.now()
    google_duo.createPost(userId, caption, imageUrl, timestamp)
    return {"message": "Post created successfully"}, 201

# High-Level API Design

class GoogleDuoAPI:
    def __init__(self):
        # Initialize any necessary components or configurations here
        pass

    def login(self, username: str, password: str) -> bool:
        # Function for user authentication
        # Implement the authentication logic here
        if username == "user" and password == "pass":
            return True
        else:
            return False

    def get_contacts(self, user_id: int) -> list:
        # Function to retrieve the list of contacts for a user
        # Implement the logic to fetch the user's contacts here
        if user_id == 12345:
            return ["Contact1", "Contact2", "Contact3"]
        else:
            return []

    def start_video_call(self, user_id: int, contact: str) -> bool:
        # Function to initiate a video call to a contact
        # Implement the logic for call initiation here
        if user_id == 12345 and contact in ["Contact1", "Contact2", "Contact3"]:
            print(f"User {user_id} is calling {contact}.")
            return True
        else:
            return False

    def get_call_status(self, user_id: int) -> str:
        # Function to retrieve the status of the ongoing call for a user
        # Implement the logic to get the call status here
        if user_id == 12345:
            return "Call in progress"
        else:
            return "No ongoing call"

# Example usage:

if __name__ == "__main__":
    google_duo = GoogleDuoAPI()

    # Sample usage of high-level API functionalities
    user_id = 12345
    username = "user"
    password = "pass"
    contact_to_call = "Contact1"

    if google_duo.login(username, password):
        print("User authentication successful.")
        contacts = google_duo.get_contacts(user_id)
        print("User's contacts:", contacts)

        if contact_to_call in contacts:
            if google_duo.start_video_call(user_id, contact_to_call):
                print(f"Call to {contact_to_call} initiated.")
                call_status = google_duo.get_call_status(user_id)
                print("Call status:", call_status)
            else:
                print("Failed to initiate the call.")
        else:
            print(f"{contact_to_call} is not in the user's contacts.")
    else:
        print("User authentication failed.")

from datetime import datetime

class UserRegistrationAuthenticationService:
    def __init__(self):
        self.users = {}
        self.next_user_id = 1

    def register_user(self, username: str, email: str, password: str) -> int:
        user_id = self.next_user_id
        self.next_user_id += 1
        self.users[user_id] = {
            'username': username,
            'email': email,
            'password': password
        }
        return user_id

    def authenticate_user(self, email: str, password: str) -> int:
        for user_id, user_data in self.users.items():
            if user_data['email'] == email and user_data['password'] == password:
                return user_id
        return -1

class ContactManagementService:
    def __init__(self):
        self.contacts = {}

    def add_contact(self, user_id: int, contact_name: str) -> bool:
        if user_id not in self.contacts:
            self.contacts[user_id] = set()
        self.contacts[user_id].add(contact_name)
        return True

    def remove_contact(self, user_id: int, contact_name: str) -> bool:
        if user_id in self.contacts and contact_name in self.contacts[user_id]:
            self.contacts[user_id].remove(contact_name)
            return True
        return False

    def search_contacts(self, user_id: int, query: str) -> list:
        if user_id in self.contacts:
            return [contact for contact in self.contacts[user_id] if query in contact]
        return []

class VideoCallService:
    def __init__(self):
        self.video_calls = {}

    def start_video_call(self, caller_id: int, receiver_id: int) -> bool:
        call_id = len(self.video_calls) + 1
        call_details = {
            'caller_id': caller_id,
            'receiver_id': receiver_id,
            'call_start_time': datetime.now(),
            'call_end_time': None
        }
        self.video_calls[call_id] = call_details
        return True

    def end_video_call(self, call_id: int) -> bool:
        if call_id in self.video_calls:
            self.video_calls[call_id]['call_end_time'] = datetime.now()
            return True
        return False

class MessageService:
    def __init__(self):
        self.messages = {}

    def send_message(self, sender_id: int, receiver_id: int, message_text: str) -> bool:
        message_id = len(self.messages) + 1
        message_details = {
            'sender_id': sender_id,
            'receiver_id': receiver_id,
            'message_text': message_text,
            'timestamp': datetime.now()
        }
        if receiver_id not in self.messages:
            self.messages[receiver_id] = []
        self.messages[receiver_id].append(message_details)
        return True

    def get_user_messages(self, user_id: int) -> list:
        if user_id in self.messages:
            return self.messages[user_id]
        return []

if __name__ == "__main__":
    # Example Usage
    user_service = UserRegistrationAuthenticationService()
    contact_service = ContactManagementService()
    video_call_service = VideoCallService()
    message_service = MessageService()

    # Register users and authenticate
    user1_id = user_service.register_user("user1", "[email protected]", "password1")
    user2_id = user_service.register_user("user2", "[email protected]", "password2")

    authenticated_user1_id = user_service.authenticate_user("[email protected]", "password1")
    authenticated_user2_id = user_service.authenticate_user("[email protected]", "password2")

    # Add contacts
    contact_service.add_contact(authenticated_user1_id, "user2")
    contact_service.add_contact(authenticated_user2_id, "user1")

    # Start a video call
    video_call_service.start_video_call(authenticated_user1_id, authenticated_user2_id)

    # Send a message
    message_service.send_message(authenticated_user1_id, authenticated_user2_id, "Hello from user1")
    message_service.send_message(authenticated_user2_id, authenticated_user1_id, "Hi from user2")

    # Get messages for a user
    user1_messages = message_service.get_user_messages(authenticated_user1_id)
    user2_messages = message_service.get_user_messages(authenticated_user2_id)

    print("User1 Messages:", user1_messages)
    print("User2 Messages:", user2_messages)

import random
import time

# Hypothetical data
total_users = 100_000_000
daily_active_users = 20_000_000
audiobooks_per_user_per_day = 2

# Function to simulate user behavior
def simulate_user_activity():
    user_id = random.randint(1, total_users)
    audiobooks_listened = random.sample(range(1, 1_000_000), audiobooks_per_user_per_day)
    return user_id, audiobooks_listened

# Function to simulate processing and reading from storage
def process_audiobook(audiobook_id):
    # Simulate processing time
    processing_time = random.uniform(0.001, 0.01)
    time.sleep(processing_time)
    return f"Audiobook {audiobook_id} processed."

if __name__ == "__main__":
    # Simulate user activity for a day
    for _ in range(daily_active_users):
        user_id, audiobooks_listened = simulate_user_activity()
        print(f"User {user_id} listened to Audiobooks: {audiobooks_listened}")

    # Simulate processing audiobooks
    for audiobook_id in range(1, 1_000_001):
        process_audiobook(audiobook_id)
        print(f"Audiobook {audiobook_id} processed.")

import uuid
import random
import time

# Simplified user and audiobook data (replace this with data from a database)
users = {
    'user1': {'username': 'user1', 'email': '[email protected]', 'password': 'password1', 'membership_level': 'silver'},
    'user2': {'username': 'user2', 'email': '[email protected]', 'password': 'password2', 'membership_level': 'gold'}
}

audiobooks = {
    'book1': {'title': 'Book 1', 'author': 'Author 1', 'genre': 'Fiction', 'duration': '5h'},
    'book2': {'title': 'Book 2', 'author': 'Author 2', 'genre': 'Fantasy', 'duration': '3h'}
}

# User Service
def register_user(username, email, password):
    user_id = str(uuid.uuid4())
    user_data = {'username': username, 'email': email, 'password': password, 'membership_level': 'free'}
    users[user_id] = user_data
    return user_id

def login_user(username, password):
    for user_id, user_data in users.items():
        if user_data['username'] == username and user_data['password'] == password:
            return user_id
    return None

# Audiobook Service
def upload_audiobook(title, author, genre, duration):
    audiobook_id = str(uuid.uuid4())
    audiobook_data = {'title': title, 'author': author, 'genre': genre, 'duration': duration}
    audiobooks[audiobook_id] = audiobook_data
    return audiobook_id

def get_audiobook_metadata(audiobook_id):
    return audiobooks.get(audiobook_id)

# Recommendation Service
def generate_personalized_recommendations(user_id):
    user_data = users.get(user_id)
    if not user_data:
        return []

    # Dummy logic: Return random audiobooks as recommendations
    recommended_audiobooks = random.sample(list(audiobooks.values()), 3)
    return recommended_audiobooks

if __name__ == '__main__':
    # User Service - Register and Login Users
    user_id1 = register_user('user1', '[email protected]', 'password1')
    user_id2 = register_user('user2', '[email protected]', 'password2')

    user_id1_login = login_user('user1', 'password1')
    user_id2_login = login_user('user2', 'password2')

    print(f"User1 ID: {user_id1}, User1 Login ID: {user_id1_login}")
    print(f"User2 ID: {user_id2}, User2 Login ID: {user_id2_login}")

    # Audiobook Service - Upload Audiobooks and Get Metadata
    audiobook_id1 = upload_audiobook('Book 1', 'Author 1', 'Fiction', '5h')
    audiobook_id2 = upload_audiobook('Book 2', 'Author 2', 'Fantasy', '3h')

    audiobook_data1 = get_audiobook_metadata(audiobook_id1)
    audiobook_data2 = get_audiobook_metadata(audiobook_id2)

    print(f"Audiobook 1 Data: {audiobook_data1}")
    print(f"Audiobook 2 Data: {audiobook_data2}")

    # Recommendation Service - Generate Personalized Recommendations
    user1_recommendations = generate_personalized_recommendations(user_id1)
    user2_recommendations = generate_personalized_recommendations(user_id2)

    print(f"User1 Recommendations: {user1_recommendations}")
    print(f"User2 Recommendations: {user2_recommendations}")

import os
from flask import Flask, request, send_file

app = Flask(__name__)

audiobooks_folder = './audiobooks/'  # Assuming audiobooks are stored in this folder

@app.route('/audiobooks/search', methods=['GET'])
def search_audiobooks():
    query = request.args.get('query')
    genre = request.args.get('genre')
    author = request.args.get('author')

    # Implement search logic based on the provided parameters
    filtered_audiobooks = [book for book in audiobooks if
                           (query.lower() in book['title'].lower() or query.lower() in book['author'].lower()) and
                           (not genre or genre.lower() == book['genre'].lower()) and
                           (not author or author.lower() == book['author'].lower())]

    if filtered_audiobooks:
        return jsonify(filtered_audiobooks), 200
    else:
        return jsonify({'message': 'No audiobooks found'}), 404

@app.route('/audiobooks/stream/<int:audiobook_id>', methods=['GET'])
def stream_audiobook(audiobook_id):
    audiobook_file = f'{audiobooks_folder}audiobook_{audiobook_id}.mp3'

    if not os.path.exists(audiobook_file):
        return jsonify({'message': 'Audiobook not found'}), 404

    return send_file(audiobook_file, as_attachment=True)

@app.route('/recommendations', methods=['GET'])
def get_recommendations():
    # Your implementation of audiobook recommendations API goes here
    pass

if __name__ == '__main__':
    app.run(debug=True)

API Design for Audible System:

User Management API:
POST /users: Create a new user account.
POST /login: Log in a user with username and password.
GET /users/{user_id}: Retrieve user information by user ID.
PATCH /users/{user_id}: Update user profile information.

Audiobooks API:
GET /audiobooks: Retrieve a list of all available audiobooks.
GET /audiobooks/{audiobook_id}: Retrieve information about a specific audiobook by audiobook ID.
POST /audiobooks: Upload a new audiobook to the platform.

Purchases API:
POST /users/{user_id}/purchases: Purchase an audiobook by a user.
GET /users/{user_id}/purchases: Retrieve the purchase history of a user.

Reviews and Ratings API:
POST /audiobooks/{audiobook_id}/reviews: Post a new review for an audiobook.
GET /audiobooks/{audiobook_id}/reviews: Retrieve all reviews for an audiobook.
POST /audiobooks/{audiobook_id}/ratings: Rate an audiobook.
GET /audiobooks/{audiobook_id}/ratings: Retrieve the average rating for an audiobook.

Explanation of APIs:

User Management API:

/users: This endpoint allows users to create a new account with a username, email, and password.
/login: Users can log in with their username and password.
/users/{user_id}: This endpoint retrieves user information by user ID.
/users/{user_id}: Users can update their profile information using this endpoint.

Audiobooks API:

/audiobooks: Users can retrieve a list of all available audiobooks.
/audiobooks/{audiobook_id}: This endpoint allows users to retrieve information about a specific audiobook by its ID.
/audiobooks: Publishers can upload new audiobooks to the platform.

Purchases API:

/users/{user_id}/purchases: Users can purchase an audiobook, associating it with their user ID.
/users/{user_id}/purchases: Retrieve the purchase history of a user.

Reviews and Ratings API:

/audiobooks/{audiobook_id}/reviews: Users can post a new review for an audiobook, associating it with the audiobook ID.
/audiobooks/{audiobook_id}/reviews: Retrieve all reviews for an audiobook.
/audiobooks/{audiobook_id}/ratings: Users can rate an audiobook, associating the rating with the audiobook ID.
/audiobooks/{audiobook_id}/ratings: Retrieve the average rating for an audiobook.

from flask import Flask, request

app = Flask(__name__)

users = []

@app.route("/users", methods=["POST"])
def create_user():
    data = request.get_json()
    new_user = {
        "user_id": len(users) + 1,
        "username": data["username"],
        "email": data["email"],
        "password": data["password"],
        "purchases": [],
        "reviews": [],
        "ratings": []
    }
    users.append(new_user)
    return {"message": "User created successfully"}, 201

@app.route("/login", methods=["POST"])
def login():
    data = request.get_json()
    for user in users:
        if user["username"] == data["username"] and user["password"] == data["password"]:
            return {"message": "Login successful"}, 200
    return {"message": "Login failed"}, 401

@app.route("/users/<int:user_id>", methods=["GET"])
def get_user(user_id):
    for user in users:
        if user["user_id"] == user_id:
            return user, 200
    return {"message": "User not found"}, 404

@app.route("/users/<int:user_id>", methods=["PATCH"])
def update_user(user_id):
    data = request.get_json()
    for user in users:
        if user["user_id"] == user_id:
            user["email"] = data["email"]
            user["password"] = data["password"]
            return {"message": "User profile updated successfully"}, 200
    return {"message": "User not found"}, 404

if __name__ == "__main__":
    app.run()

# Sample data for audiobook library 
audiobook_library = [
    {
        'title': 'Book1',
        'author': 'Author1',
        'genre': 'Fiction',
        'platform_support': ['smartphone', 'tablet', 'computer', 'smart_speaker'],
        'offline_listening': True,
        'whispersync_for_voice': True
    },
    {
        'title': 'Book2',
        'author': 'Author2',
        'genre': 'Fantasy',
        'platform_support': ['smartphone', 'tablet', 'computer'],
        'offline_listening': True,
        'whispersync_for_voice': False
    },
    # Add more audiobooks...
]

# Sample data for user listening history and preferences (replace this with actual user data from a database)
user_data = {
    'user1': {
        'listening_history': ['Book1', 'Book2'],
        'preferences': {'genre': 'Fiction', 'platform': 'smartphone'}
    },
    'user2': {
        'listening_history': ['Book1'],
        'preferences': {'genre': 'Fantasy', 'platform': 'tablet'}
    },
    # Add more users' data...
}

# Function to get personalized audiobook recommendations for a user
def get_personalized_recommendations(user_id):
    user_preferences = user_data.get(user_id)
    if not user_preferences:
        return []

    genre_preference = user_preferences['preferences']['genre']
    platform_preference = user_preferences['preferences']['platform']

    recommendations = []
    for audiobook in audiobook_library:
        if audiobook['genre'] == genre_preference and platform_preference in audiobook['platform_support']:
            recommendations.append(audiobook)

    return recommendations

# Function to check if a user can use Whispersync for Voice feature
def can_use_whispersync_for_voice(user_id):
    user_listening_history = user_data.get(user_id, {}).get('listening_history', [])
    return all(audiobook['whispersync_for_voice'] for audiobook in audiobook_library if audiobook['title'] in user_listening_history)

# Function to get the membership benefits for a user
def get_membership_benefits(user_id):
    # Sample benefits for different membership tiers (replace this with actual benefits data from a database)
    membership_tiers = {
        'free': {'monthly_credits': 0, 'exclusive_discounts': False, 'access_to_originals': False},
        'silver': {'monthly_credits': 1, 'exclusive_discounts': False, 'access_to_originals': False},
        'gold': {'monthly_credits': 2, 'exclusive_discounts': True, 'access_to_originals': False},
        'platinum': {'monthly_credits': 2, 'exclusive_discounts': True, 'access_to_originals': True},
    }

    user_membership_tier = 'free'  # Replace this with actual user membership tier data from a database
    return membership_tiers.get(user_membership_tier, {})

if __name__ == '__main__':
    # Sample usage of the functions
    user_id = 'user1'
    print(f"Personalized Recommendations for {user_id}: {get_personalized_recommendations(user_id)}")

    print(f"Can {user_id} use Whispersync for Voice? {can_use_whispersync_for_voice(user_id)}")

    print(f"Membership Benefits for {user_id}: {get_membership_benefits(user_id)}")

import random

class User:
    def __init__(self, user_id, name):
        self.user_id = user_id
        self.name = name

class Pokemon:
    def __init__(self, pokemon_id, name, type_, cp, hp, owner_id):
        self.pokemon_id = pokemon_id
        self.name = name
        self.type = type_
        self.cp = cp
        self.hp = hp
        self.owner_id = owner_id

def catch_pokemon(user, pokemon_id, name, type_, cp, hp):
    new_pokemon = Pokemon(pokemon_id, name, type_, cp, hp, user.user_id)
    # Store the new Pokémon in the database or in-memory data structure.

def spawn_pokemon():
    pokemon_id = random.randint(1, 151)  # Assuming 151 Pokémon in the game.
    name = f"Pokemon{pokemon_id}"
    type_ = "Normal"  # For simplicity, let's assume all spawned Pokémon have the "Normal" type.
    cp = random.randint(10, 1000)
    hp = random.randint(10, 200)
    return pokemon_id, name, type_, cp, hp

def get_user_pokemons(user):
    # Retrieve and return all Pokémon caught by the user from the database or in-memory data structure.
    pass

if __name__ == "__main__":
    users = [User(user_id, f"User{user_id}") for user_id in range(1, 201)]  # Create 200 users.

    # Simulating catching Pokémon by users.
    for user in users:
        for _ in range(10):
            pokemon_id, name, type_, cp, hp = spawn_pokemon()
            catch_pokemon(user, pokemon_id, name, type_, cp, hp)

    # Displaying the Pokémon caught by each user.
    for user in users:
        user_pokemons = get_user_pokemons(user)
        print(f"{user.name}'s Pokémon:")
        for pokemon in user_pokemons:
            print(f"- {pokemon.name} (Type: {pokemon.type}, CP: {pokemon.cp}, HP: {pokemon.hp})")

class User:
    def __init__(self, user_id, username, password):
        self.user_id = user_id
        self.username = username
        self.password = password
        # Other user attributes

class Pokemon:
    def __init__(self, pokemon_id, name, type_, cp, hp, owner):
        self.pokemon_id = pokemon_id
        self.name = name
        self.type = type_
        self.cp = cp
        self.hp = hp
        self.owner = owner
        # Other Pokemon attributes

class PokemonGo:
    def __init__(self):
        self.users = {}
        self.pokemons = []

    def add_user(self, user):
        self.users[user.user_id] = user

    def get_user_by_id(self, user_id):
        return self.users.get(user_id)

    def capture_pokemon(self, user_id, name, type_, cp, hp):
        user = self.get_user_by_id(user_id)
        if user is None:
            print("User not found")
            return

        pokemon_id = len(self.pokemons) + 1
        pokemon = Pokemon(pokemon_id, name, type_, cp, hp, user)
        self.pokemons.append(pokemon)

    def get_pokemon_details(self, pokemon_id):
        for pokemon in self.pokemons:
            if pokemon.pokemon_id == pokemon_id:
                return {
                    "pokemon_id": pokemon.pokemon_id,
                    "name": pokemon.name,
                    "type": pokemon.type,
                    "cp": pokemon.cp,
                    "hp": pokemon.hp,
                    "owner": {
                        "user_id": pokemon.owner.user_id,
                        "username": pokemon.owner.username
                    }
                }
        return None

if __name__ == "__main__":
    pokemon_go = PokemonGo()

    user1 = User(1, "Ash Ketchum", "pikachu123")
    pokemon_go.add_user(user1)

    pokemon_go.capture_pokemon(user_id=1, name="Pikachu", type_="Electric", cp=100, hp=50)

    pokemon_details = pokemon_go.get_pokemon_details(pokemon_id=1)
    if pokemon_details:
        print("Pokemon Details:")
        print(pokemon_details)
    else:
        print("Pokemon not found")

from flask import Flask, request, jsonify

app = Flask(__name__)

class User:
    def __init__(self, user_id, username, password):
        self.user_id = user_id
        self.username = username
        self.password = password
        # Other user attributes

class Pokemon:
    def __init__(self, pokemon_id, name, type_, cp, hp, owner):
        self.pokemon_id = pokemon_id
        self.name = name
        self.type = type_
        self.cp = cp
        self.hp = hp
        self.owner = owner
        # Other Pokemon attributes

class PokemonGo:
    def __init__(self):
        self.users = {}
        self.pokemons = []

    # API endpoint for adding a new user
    def add_user(self, user):
        self.users[user.user_id] = user

    # API endpoint for capturing a new Pokemon
    def capture_pokemon(self, user_id, name, type_, cp, hp):
        user = self.get_user_by_id(user_id)
        if user is None:
            return "User not found", 404

        pokemon_id = len(self.pokemons) + 1
        pokemon = Pokemon(pokemon_id, name, type_, cp, hp, user)
        self.pokemons.append(pokemon)
        return "Pokemon captured successfully", 201

    def get_user_by_id(self, user_id):
        return self.users.get(user_id)

    # API endpoint for retrieving Pokemon details
    def get_pokemon_details(self, pokemon_id):
        for pokemon in self.pokemons:
            if pokemon.pokemon_id == pokemon_id:
                return {
                    "pokemon_id": pokemon.pokemon_id,
                    "name": pokemon.name,
                    "type": pokemon.type,
                    "cp": pokemon.cp,
                    "hp": pokemon.hp,
                    "owner": {
                        "user_id": pokemon.owner.user_id,
                        "username": pokemon.owner.username
                    }
                }
        return "Pokemon not found", 404

# Create an instance of PokemonGo
pokemon_go = PokemonGo()

# Endpoint for capturing a new Pokemon
@app.route('/pokemon/capture', methods=['POST'])
def capture_pokemon():
    data = request.get_json()
    user_id = data.get('user_id')
    name = data.get('name')
    type_ = data.get('type')
    cp = data.get('cp')
    hp = data.get('hp')
    response, status_code = pokemon_go.capture_pokemon(user_id, name, type_, cp, hp)
    return jsonify(response), status_code

# Endpoint for retrieving Pokemon details
@app.route('/pokemon/<int:pokemon_id>', methods=['GET'])
def get_pokemon_details(pokemon_id):
    response, status_code = pokemon_go.get_pokemon_details(pokemon_id)
    return jsonify(response), status_code

if __name__ == '__main__':
    app.run(debug=True)

import requests

# Endpoint for capturing a new Pokemon
def capture_pokemon(user_id, name, type_, cp, hp):
    url = 'http://127.0.0.1:5000/pokemon/capture'
    data = {
        "user_id": user_id,
        "name": name,
        "type": type_,
        "cp": cp,
        "hp": hp
    }
    response = requests.post(url, json=data)
    if response.status_code == 201:
        print("Pokemon captured successfully!")
    else:
        print("Failed to capture Pokemon.")

# Example usage
capture_pokemon(user_id=1, name="Pikachu", type_="Electric", cp=100, hp=50)

import requests

# Endpoint for retrieving Pokemon details
def get_pokemon_details(pokemon_id):
    url = f'http://127.0.0.1:5000/pokemon/{pokemon_id}'
    response = requests.get(url)
    if response.status_code == 200:
        pokemon_details = response.json()
        print("Pokemon Details:")
        print(pokemon_details)
    else:
        print("Pokemon not found.")

# Example usage
get_pokemon_details(pokemon_id=1)

class Player:
    def __init__(self, player_id, name, team):
        self.player_id = player_id
        self.name = name
        self.team = team
        self.inventory = {}

    def update_name(self, new_name):
        self.name = new_name

    def add_item_to_inventory(self, item_id, quantity):
        if item_id in self.inventory:
            self.inventory[item_id] += quantity
        else:
            self.inventory[item_id] = quantity

    def remove_item_from_inventory(self, item_id, quantity):
        if item_id in self.inventory:
            self.inventory[item_id] -= quantity
            if self.inventory[item_id] <= 0:
                del self.inventory[item_id]

# Example Usage:
player1 = Player(1, "Ash Ketchum", "Mystic")
player1.add_item_to_inventory("pokeball", 10)
player1.update_name("Ash K.")

class Pokemon:
    def __init__(self, pokemon_id, name, type_, cp, hp, owner_id):
        self.pokemon_id = pokemon_id
        self.name = name
        self.type = type_
        self.cp = cp
        self.hp = hp
        self.owner_id = owner_id

# Function to catch a new Pokémon
def catch_pokemon(player, pokemon_id, name, type_, cp, hp):
    new_pokemon = Pokemon(pokemon_id, name, type_, cp, hp, player.player_id)
    # Add the new Pokémon to the player's inventory or database.

# Function to get all Pokémon of a player
def get_player_pokemons(player):
    player_pokemons = []  # Retrieve Pokémon data from the player's inventory or database.
    return player_pokemons

# Example Usage:
catch_pokemon(player1, 25, "Pikachu", "Electric", 1200, 100)
player1_pokemons = get_player_pokemons(player1)

class PokeStop:
    def __init__(self, stop_id, location):
        self.stop_id = stop_id
        self.location = location

# Function to spin a PokéStop
def spin_pokestop(player, pokestop):
    # Retrieve items from the PokéStop and add them to the player's inventory.

# Example Usage:
pokestop1 = PokeStop(101, "Coordinates of PokéStop 1")
spin_pokestop(player1, pokestop1)

from flask import Flask, request, jsonify

app = Flask(__name__)

# Player Management API
@app.route("/player", methods=["POST"])
def register_player():
    data = request.json
    player_id = data["player_id"]
    name = data["name"]
    team = data["team"]
    player = Player(player_id, name, team)
    # Store the player in the database or in-memory data structure.
    return jsonify({"message": "Player registered successfully!"})

@app.route("/player/<int:player_id>", methods=["GET"])
def get_player(player_id):
    # Fetch player details from the database or in-memory data structure.
    return jsonify(player_details)

@app.route("/player/<int:player_id>", methods=["PUT"])
def update_player(player_id):
    data = request.json
    new_name = data["name"]
    # Update the player's name in the database or in-memory data structure.
    return jsonify({"message": "Player name updated successfully!"})

# Pokémon Management API
@app.route("/pokemon/catch", methods=["POST"])
def catch_pokemon_endpoint():
    data = request.json
    player_id = data["player_id"]
    pokemon_id = data["pokemon_id"]
    name = data["name"]
    type_ = data["type"]
    cp = data["cp"]
    hp = data["hp"]
    player = get_player_by_id(player_id)
    if not player:
        return jsonify({"error": "Player not found"}), 404
    catch_pokemon(player, pokemon_id, name, type_, cp, hp)
    return jsonify({"message": "Pokémon caught successfully!"})

@app.route("/pokemon/<int:player_id>", methods=["GET"])
def get_player_pokemons_endpoint(player_id):
    player = get_player_by_id(player_id)
    if not player:
        return jsonify({"error": "Player not found"}), 404
    player_pokemons = get_player_pokemons(player)
    return jsonify(player_pokemons)

# PokéStops API
@app.route("/pokestop/<int:player_id>", methods=["POST"])
def spin_pokestop_endpoint(player_id):
    player = get_player_by_id(player_id)
    if not player:
        return jsonify({"error": "Player not found"}), 404
    pokestop = get_closest_pokestop(player.location)
    spin_pokestop(player, pokestop)
    return jsonify({"message": "PokéStop spun successfully!"})

if __name__ == "__main__":
    app.run()

import random

class Player:
    def __init__(self, player_id, name, team):
        self.player_id = player_id
        self.name = name
        self.team = team
        self.inventory = {}

class Pokemon:
    def __init__(self, pokemon_id, name, type_, cp, hp, owner_id):
        self.pokemon_id = pokemon_id
        self.name = name
        self.type = type_
        self.cp = cp
        self.hp = hp
        self.owner_id = owner_id

def catch_pokemon(player, pokemon_id, name, type_, cp, hp):
    new_pokemon = Pokemon(pokemon_id, name, type_, cp, hp, player.player_id)
    add_pokemon_to_inventory(player, new_pokemon)

def add_pokemon_to_inventory(player, pokemon):
    if 'pokemons' not in player.inventory:
        player.inventory['pokemons'] = []
    player.inventory['pokemons'].append(pokemon)

def get_player_pokemons(player):
    if 'pokemons' not in player.inventory:
        return []
    return player.inventory['pokemons']

if __name__ == "__main__":
    player1 = Player(1, "Ash Ketchum", "Mystic")
    player2 = Player(2, "Gary Oak", "Valor")

    # Simulating catching Pokémon by player1 and player2
    catch_pokemon(player1, 25, "Pikachu", "Electric", 1200, 100)
    catch_pokemon(player2, 7, "Squirtle", "Water", 900, 80)
    catch_pokemon(player2, 4, "Charmander", "Fire", 1000, 90)

    # Displaying the captured Pokémon for each player
    player1_pokemons = get_player_pokemons(player1)
    player2_pokemons = get_player_pokemons(player2)

    print(f"{player1.name}'s Pokémons:")
    for pokemon in player1_pokemons:
        print(f"- {pokemon.name} (Type: {pokemon.type}, CP: {pokemon.cp}, HP: {pokemon.hp})")

    print(f"{player2.name}'s Pokémons:")
    for pokemon in player2_pokemons:
        print(f"- {pokemon.name} (Type: {pokemon.type}, CP: {pokemon.cp}, HP: {pokemon.hp})")

import random

class User:
    def __init__(self, user_id):
        self.user_id = user_id

    def watch_meditation_session(self):
        # Simulating watching a meditation session
        return random.randint(1, 100)

class MeditationSession:
    def __init__(self, session_id, title, duration, instructor, theme):
        self.session_id = session_id
        self.title = title
        self.duration = duration
        self.instructor = instructor
        self.theme = theme

class Storage:
    def __init__(self):
        self.users = {}
        self.meditation_sessions = {}

    def add_user(self, user):
        self.users[user.user_id] = user

    def add_meditation_session(self, meditation_session):
        self.meditation_sessions[meditation_session.session_id] = meditation_session

    def get_user(self, user_id):
        return self.users.get(user_id)

    def get_meditation_session(self, session_id):
        return self.meditation_sessions.get(session_id)

# Simulation
storage = Storage()

# Adding users to the system
for user_id in range(1, 1200000000):
    user = User(user_id)
    storage.add_user(user)

# Adding meditation sessions to the system
for session_id in range(1, 900000001):
    session = MeditationSession(session_id, "Meditation Title", "20 minutes", "John Doe", "Stress Reduction")
    storage.add_meditation_session(session)

# Simulating user activity for a day
total_views = 0
for user_id in range(1, 300000001):
    user = storage.get_user(user_id)
    for _ in range(3):
        meditation_session_id = user.watch_meditation_session()
        meditation_session = storage.get_meditation_session(meditation_session_id)
        if meditation_session:
            total_views += 1

print(f"Total meditation sessions watched per day: {total_views}")

# Low-Level API Design using Flask (without Flask-RESTful)

from flask import Flask, request, jsonify

app = Flask(__name__)

# In a real application, the user data would be stored securely in a database
# For demonstration purposes, we'll use a simple dictionary to store user data
users = {
    "[email protected]": {
        "user_id": "12345",
        "password": "user_password"
    }
}

@app.route('/api/auth/login', methods=['POST'])
def login():
    data = request.get_json()
    email = data.get('email')
    password = data.get('password')
    user = users.get(email)
    if user and user['password'] == password:
        # In a real application, generate and return a secure access token using a library like PyJWT
        access_token = "generated_access_token"
        response = {
            "user_id": user['user_id'],
            "access_token": access_token,
            "token_type": "Bearer"
        }
        return jsonify(response), 200
    else:
        return jsonify({"message": "Invalid credentials"}), 401

@app.route('/api/meditations/<meditation_id>', methods=['GET'])
def get_meditation(meditation_id):
    # In a real application, retrieve meditation details from the database
    # For demonstration purposes, we'll use a simple dictionary to store meditation data
    meditations = {
        "123": {
            "meditation_id": "123",
            "title": "Mindfulness Meditation",
            "duration": "20 minutes",
            "instructor": "John Doe",
            "theme": "Stress Reduction"
        }
    }
    meditation = meditations.get(meditation_id)
    if meditation:
        return jsonify(meditation), 200
    else:
        return jsonify({"message": "Meditation not found"}), 404

if __name__ == '__main__':
    app.run(debug=True)

# High-Level API Design using Flask-RESTful

from flask import Flask
from flask_restful import Api, Resource, reqparse

app = Flask(__name__)
api = Api(app)

# In a real application, the user data would be stored securely in a database
# For demonstration purposes, we'll use a simple dictionary to store user data
users = {
    "[email protected]": {
        "user_id": "12345",
        "password": "user_password"
    }
}

class UserLogin(Resource):
    def post(self):
        parser = reqparse.RequestParser()
        parser.add_argument('email', type=str, required=True)
        parser.add_argument('password', type=str, required=True)
        data = parser.parse_args()
        email = data['email']
        password = data['password']
        user = users.get(email)
        if user and user['password'] == password:
            # In a real application, generate and return a secure access token using a library like PyJWT
            access_token = "generated_access_token"
            response = {
                "user_id": user['user_id'],
                "access_token": access_token,
                "token_type": "Bearer"
            }
            return response, 200
        else:
            return {"message": "Invalid credentials"}, 401

api.add_resource(UserLogin, '/api/auth/login')

class Meditation(Resource):
    def get(self, meditation_id):
        # In a real application, retrieve meditation details from the database
        # For demonstration purposes, we'll use a simple dictionary to store meditation data
        meditations = {
            "123": {
                "meditation_id": "123",
                "title": "Mindfulness Meditation",
                "duration": "20 minutes",
                "instructor": "John Doe",
                "theme": "Stress Reduction"
            }
        }
        meditation = meditations.get(meditation_id)
        if meditation:
            return meditation, 200
        else:
            return {"message": "Meditation not found"}, 404

api.add_resource(Meditation, '/api/meditations/<string:meditation_id>')

if __name__ == '__main__':
    app.run(debug=True)

class User:
    def __init__(self, user_id, username, email, password):
        self.user_id = user_id
        self.username = username
        self.email = email
        self.password = password
        # Other user attributes (e.g., preferences, settings, etc.)

class MeditationSession:
    def __init__(self, session_id, user_id, photo_url, caption, post_timestamp, location):
        self.session_id = session_id
        self.user_id = user_id
        self.photo_url = photo_url
        self.caption = caption
        self.post_timestamp = post_timestamp
        self.location = location
        # Other meditation session attributes

class Like:
    def __init__(self, like_id, user_id, session_id, timestamp):
        self.like_id = like_id
        self.user_id = user_id
        self.session_id = session_id
        self.timestamp = timestamp
        # Other like attributes

class Comment:
    def __init__(self, comment_id, user_id, session_id, caption_text, timestamp):
        self.comment_id = comment_id
        self.user_id = user_id
        self.session_id = session_id
        self.caption_text = caption_text
        self.timestamp = timestamp
        # Other comment attributes

class Follow:
    def __init__(self, follower_id, followed_id):
        self.follower_id = follower_id
        self.followed_id = followed_id