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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 flushOutBoxes(self) -> None: """ Clear the outBoxes and transmit batched messages to remotes. """

        removedRemotes = []
        for rid, msgs in self.outBoxes.items():
            try:
                dest = self.remotes[rid].name
            except KeyError:
                removedRemotes.append(rid)
                continue
            if msgs:
                if self._should_batch(msgs):
                    logger.trace(
                        "{} batching {} msgs to {} into fewer transmissions".
                        format(self, len(msgs), dest))
                    logger.trace("    messages: {}".format(msgs))
                    batches = split_messages_on_batches(list(msgs),
                                                        self._make_batch,
                                                        self._test_batch_len,
                                                        )
                    msgs.clear()
                    if batches:
                        for batch, size in batches:
                            logger.trace("{} sending payload to {}: {}".format(
                                self, dest, batch))
                            self.metrics.add_event(MetricsName.TRANSPORT_BATCH_SIZE, size)
                            # Setting timeout to never expire
                            self.transmit(
                                batch,
                                rid,
                                timeout=self.messageTimeout,
                                serialized=True)
                    else:
                        logger.error("{} cannot create batch(es) for {}".format(self, dest))
                else:
                    while msgs:
                        msg = msgs.popleft()
                        logger.trace(
                            "{} sending msg {} to {}".format(self, msg, dest))
                        self.metrics.add_event(MetricsName.TRANSPORT_BATCH_SIZE, 1)
                        # Setting timeout to never expire
                        self.transmit(msg, rid, timeout=self.messageTimeout,
                                      serialized=True)

        for rid in removedRemotes:
            logger.warning("{}{} has removed rid {}"
                           .format(CONNECTION_PREFIX, self,
                                   z85_to_friendly(rid)),
                           extra={"cli": False})
            msgs = self.outBoxes[rid]
            if msgs:
                self.discard(msgs,
                             "{}rid {} no longer available"
                             .format(CONNECTION_PREFIX,
                                     z85_to_friendly(rid)),
                             logMethod=logger.debug)
            del self.outBoxes[rid]