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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def rooms(sid=None, namespace=None):
 """Return a list of the rooms the client is in. This function returns all the rooms the client has entered, including its own room, assigned by the Socket.IO server. :param sid: The session id of the client. If not provided, the client is obtained from the request context. :param namespace: The namespace for the room. If not provided, the namespace is obtained from the request context. """

    socketio = flask.current_app.extensions['socketio']
    sid = sid or flask.request.sid
    namespace = namespace or flask.request.namespace
    return socketio.server.rooms(sid, namespace=namespace)