Working with asyncio and sync worker processes is always a pain, not anymore with Janus and this convertor. Async -> Sync is also trivial to implement.

sync_to_async_queue.py

from queue import Queue
from threading import Thread
from typing import cast
import asyncio
import janus

# note that this will never cleanup the thread. You will need to implement your own shutdown logic / methods.

def sync_to_async_queue(queue: Queue, loop: asyncio.AbstractEventLoop) -> asyncio.Queue:
    conversion_queue: janus.Queue = janus.Queue(loop=loop)

    def listen_and_forward(queue_to_watch: Queue) -> None:
        while True:
            try:
                conversion_queue.sync_q.put(queue_to_watch.get())
            except Exception:
                return

    thread = Thread(target=listen_and_forward, args=(queue,), daemon=True)
    thread.start()
    return cast(asyncio.Queue, conversion_queue.async_q)