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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 on_ping(self, data):
 """ Called when the client pings our websocket connection. We proxy it to the backend. """

        self.log.debug('jupyter_server_proxy: on_ping: {}'.format(data))
        self._record_activity()
        if hasattr(self, 'ws'):
            self.ws.protocol.write_ping(data)