Build a Chat RoomStep 3 of 5

Private Messages

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Step 3: Private Messages

The mediator can route messages, not just broadcast them. Add directed delivery so a user can message exactly one other user by name.

Implement ChatRoom.send_private(sender, target_name, message). It must deliver the message only to the registered user whose name equals target_name, by appending it to that user's inbox. If no registered user has that name, do nothing and raise no error.

Only the named target receives the message; nobody else does.

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

    def send(self, message):
        self.room.broadcast(self, message)


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)

    def send_private(self, sender, target_name, message):
        """Deliver message only to the user named target_name."""
        # TODO: find the user whose name matches target_name and append
        # the message to that user's inbox; ignore an unknown target
        pass
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