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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 start(self, **kwargs):
 """Start listening to command queue, process commands in main loop, This function is most likely called by the frontend in a separate process."""


        # Keep a copy of keyword arguments for use in subclasses
        self.start_kwargs.update(kwargs)
        try:
            self.initialize_logging()

            self.__update_service_status(self.SERVICE_STATUS_STARTING)

            self.start_transport()

            self.initializing()
            self._register("command", self.__process_command)

            if self.__pipe_commands is None:
                # can only listen to commands if command queue is defined
                self.__shutdown = True
            else:
                # start listening to command queue in separate thread
                self.__start_command_queue_listener()

            while not self.__shutdown:  # main loop
                self.__update_service_status(self.SERVICE_STATUS_IDLE)

                if self._idle_time is None:
                    task = self.__queue.get()
                else:
                    try:
                        task = self.__queue.get(True, self._idle_time)
                    except queue.Empty:
                        self.__update_service_status(self.SERVICE_STATUS_TIMER)
                        if self._idle_callback:
                            self._idle_callback()
                        continue

                self.__update_service_status(self.SERVICE_STATUS_PROCESSING)

                if task[0] == Priority.COMMAND:
                    message = task[2]
                    if message and "band" in message:
                        processor = self.__callback_register.get(message["band"])
                        if processor is None:
                            self.log.warning(
                                "received message on unregistered band\n%s", message
                            )
                        else:
                            processor(message.get("payload"))
                    else:
                        self.log.warning(
                            "received message without band information\n%s", message
                        )
                elif task[0] == Priority.TRANSPORT:
                    callback, header, message = task[2]
                    callback(header, message)
                else:
                    self.log.warning("Unknown item on main service queue\n%r", task)

        except KeyboardInterrupt:
            self.log.warning("Ctrl+C detected. Shutting down.")

        except Exception as e:
            self.process_uncaught_exception(e)
            self.__update_service_status(self.SERVICE_STATUS_ERROR)
            self.in_shutdown()
            return

        try:
            self.__update_service_status(self.SERVICE_STATUS_SHUTDOWN)
            self.in_shutdown()
            self.__update_service_status(self.SERVICE_STATUS_END)
        except Exception as e:
            self.process_uncaught_exception(e)
            self.__update_service_status(self.SERVICE_STATUS_ERROR)