Design a simplified version of Twitter, where users can post tweets, follow/unfollow others, and is able to see the 10 most recent tweets in the user’s news feed.

simple_twitter.py

from time import time
from pprint import pprint

def postTweet(userid, tweet):
    """
    """
    tweets.append({"message": tweet, "userid": userid, "creationTime": time()})

def follow(follower, followee):
    """
    add followee id to follower's following list.
    """
    follower["following"].append(followee["id"])

def unfollow(follower, followee):
    """
    """
    follower["following"].remove(followee["id"])

def getNewsFeed(userid):
    """
    return 10 most recent tweets from the following list for user
    """
    feed = []
    user = getUserById(userid)
    for tweet in sorted(tweets, key=lambda tweet: tweet["creationTime"], reverse=True):
        if tweet["userid"] in user["following"]:
            feed.append(tweet)
        if len(feed) == 10:
            break
    return feed

def addUser(id):
    users.append({"id": id, "following": []})

def getUserById(userid):
    for user in users:
        if user["id"] == userid:
            return user

users = []
tweets = []

def main():
    addUser(1)
    addUser(2)
    addUser(3)

    follow(users[0], users[1])
    follow(users[1], users[0])
    follow(users[1], users[2])

    postTweet(users[0]["id"], "My first tweet")
    postTweet(users[1]["id"], "My first tweet")
    postTweet(users[2]["id"], "My first tweet")
    postTweet(users[0]["id"], "My second tweet")
    postTweet(users[1]["id"], "My second tweet")
    postTweet(users[2]["id"], "My second tweet")
    postTweet(users[0]["id"], "My third tweet")
    postTweet(users[1]["id"], "My third tweet")
    postTweet(users[2]["id"], "My third tweet")
    postTweet(users[0]["id"], "My fourth tweet")
    postTweet(users[1]["id"], "My fourth tweet")
    postTweet(users[2]["id"], "My fourth tweet")
    postTweet(users[0]["id"], "My fifth tweet")
    postTweet(users[1]["id"], "My fifth tweet")
    postTweet(users[2]["id"], "My fifth tweet")
    postTweet(users[0]["id"], "My sixth tweet")
    postTweet(users[1]["id"], "My sixth tweet")
    postTweet(users[2]["id"], "My sixth tweet")

    print(f"User {users[1]} feed:")
    pprint(getNewsFeed(users[1]["id"]))

if __name__ == '__main__':
    main()