[Python] Is a lock needed when multiple tasks push into the same asyncio Queue?

Consider this example where I have 3 worker tasks that push results in a queue and a tasks that deals with the pushed data.


async def worker1(queue: asyncio.Queue):
while True:
res = await do_some_work(param=1)

await queue.put(res)

async def worker2(queue: asyncio.Queue):
while True:
res = await do_some_work(param=2)

await queue.put(res)

async def worker3(queue: asyncio.Queue):
while True:
res = await do_some_work(param=3)

await queue.put(res)

async def handle_results(queue: asyncio.Queue):

while True:
res = await queue.get()
await handle_result(res)
queue.task_done()

async def main():
queue = asyncio.Queue()
t1 = asyncio.create_task(worker1(queue))
t2 = asyncio.create_task(worker2(queue))
t3 = asyncio.create_task(worker3(queue))

handler = asyncio.create_task(handle_result(queue))

while True:
# do some other stuff

....

asyncio.run(main())



The documentation says that asyncio.Queue is not thread-safe, but this should not apply here because all tasks are running in the same thread. But do I need an asyncio.Lock to protect the queue when I have 3 tasks that push into the same queue? Looking at the implementation in Python 3.12 (which creates a putter future and awaits on it before pushing into the queue) I would say no, but I'm not sure and the documentation does not mention what would happen in this case. So, is the asyncio.Lock in this case necessary?

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