Build a Chat RoomStep 2 of 5

Users Send Through the Room

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Step 2: Users Send Through the Room

A user should never reach into another user directly. When a user wants to talk, it asks the mediator to do the work. This is the heart of the pattern: the User is decoupled from every other User and only knows about its room.

Implement User.send(message). It must ask the room to broadcast the message on this user's behalf, passing this user as the sender.

Because broadcast already skips the sender, calling send delivers the message to everyone else and never back to the caller.

Hints
Starter code
class User:
    def __init__(self, name):
        self.name = name
        self.inbox = []
        self.room = None

    def send(self, message):
        """Ask the room to broadcast this message on the user's behalf."""
        # TODO: call self.room.broadcast with this user as the sender
        pass


class ChatRoom:
    def __init__(self):
        self.users = []

    def register(self, user):
        self.users.append(user)
        user.room = self

    def broadcast(self, sender, message):
        for user in self.users:
            if user is not sender:
                user.inbox.append(message)
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