You are given a list of airline tickets where tickets[i] = [fromi, toi] represent the departure and the arrival airports of one flight. Reconstruct the itinerary in order and return it.

Design a simplified version of Twitter where users can post tweets, follow/unfollow another user, and see the 10 most recent tweets in their news feed. Implement the Twitter class with postTweet, getNewsFeed, follow, and unfollow methods.