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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 process_transport_command(self, header, message):
 """Parse a command coming in through the transport command subscription"""

        if not isinstance(message, dict):
            return

        relevant = False
        if "host" in message:  # Filter by host
            if message["host"] != self.__hostid:
                return
            relevant = True
        if "service" in message:  # Filter by service
            if message["service"] != self._service_class_name:
                return
            relevant = True
        if not relevant:  # Ignore message unless at least one filter matches
            return

        if message.get("command"):
            self.log.info(
                "Received command '%s' via transport layer", message["command"]
            )
            if message["command"] == "shutdown":
                self.shutdown = True
        else:
            self.log.warning("Received invalid transport command message")