QueuePipe joins forwards messages from one theading queue to another, can be stopped by invoking the stop() method.

queue_pipe.py

from queue import Queue
from threading import Thread


class KillSignal:
    pass


class QueuePipe:
    def __init__(self, queue_in: Queue, queue_out: Queue) -> None:
        self._queue_in = queue_in
        self._queue_out = queue_out
        self.thread = Thread(target=self._pipe, args=(self._queue_in, self._queue_out,))
        self.thread.start()

    def _pipe(self, queue_in: Queue, queue_out: Queue) -> None:
        while True:
            mes_in = queue_in.get()
            queue_out.put(mes_in)
            if isinstance(mes_in, KillSignal):
                return

    def stop(self) -> None:
        self._queue_in.put(KillSignal())