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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 send(self, message):
 """Publish a command string to the gateway via MQTT."""

        if not message:
            return
        topic, payload, qos = self._parse_message_to_mqtt(message)
        try:
            _LOGGER.debug('Publishing %s', message.strip())
            self._pub_callback(topic, payload, qos, self._retain)
        except Exception as exception:  # pylint: disable=broad-except
            _LOGGER.exception('Publish to %s failed: %s', topic, exception)