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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 ping(self):
 """ Send a ping message. """

        self.last_ping = time.time()
        try:
            self.send_message({MESSAGE_TYPE: TYPE_PING})
        except NotConnected:
            self._socket_client.logger.error("Chromecast is disconnected. " +
                                             "Cannot ping until reconnected.")