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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 disconnect(sid=None, namespace=None, silent=False):
 """Disconnect the client. This function terminates the connection with the client. As a result of this call the client will receive a disconnect event. Example:: @socketio.on('message') def receive_message(msg):
 if is_banned(session['username']):
 disconnect() else: :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. :param silent: this option is deprecated. """

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