Is this a good example of the mediator pattern?

Question

Python

Here is an example using the mediator pattern:

class ChatRoom(object):
    """Mediator class"""

    def display_message(self, user, message):
        print("[{} says]: {}".format(user, message))


class User(object):
    """A class whose instances want to interact with each other"""

    def __init__(self, name):
        self.name = name
        self.chat_room = ChatRoom()

    def say(self, message):
        self.chat_room.display_message(self, message)

    def __str__(self):
        return self.name


def main():
    molly = User('Molly')
    mark = User('Mark')
    ethan = User('Ethan')

    molly.say("Hi Team! Meeting at 3 PM today.")
    mark.say("Roger that!")
    ethan.say("Alright.")


if __name__ == '__main__':
    main()

Please tell me if this is a good example to illustrate how this pattern works? Two things confuse me:
1. the mediator object does not exist in a single instance
2. objects of the User class do not interact with each other, and the mediator should help exactly in this
ps:
The fact is that I'm looking for a clear and illustrative example of this pattern, the given solution by far the most confusing in my opinion