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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_scan_request(self, sequence, topic, message):
 """Process a request for scanning information Args: sequence (int:) The sequence number of the packet received topic (string):
 The topic this message was received on message_type (string):
 The type of the packet received message (dict):
 The message itself """


        if messages.ProbeCommand.matches(message):
            self._logger.debug("Received probe message on topic %s, message=%s", topic, message)
            self._loop.add_callback(self._publish_scan_response, message['client'])
        else:
            self._logger.warn("Invalid message received on topic %s, message=%s", topic, message)