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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:
 async def start(self):
 """Starts receiving messages on the underlying socket and passes them to the message router. """

        self._is_running = True

        while self._is_running:
            try:
                zmq_msg = await self._socket.recv_multipart()

                message = Message()
                message.ParseFromString(zmq_msg[-1])

                await self._msg_router.route_msg(message)
            except DecodeError as e:
                LOGGER.warning('Unable to decode: %s', e)
            except zmq.ZMQError as e:
                LOGGER.warning('Unable to receive: %s', e)
                return
            except asyncio.CancelledError:
                self._is_running = False