This demonstrates why asyncio.wait_for should never be used with loop.run_in_executor. Cancellation doesn't cross that boundary.

buggy_timeout.py

import time
import asyncio


def blocking():
    time.sleep(5)
    print("hell yeah")


async def main():
    loop = asyncio.get_event_loop()
    fut = loop.run_in_executor(None, blocking)
    try:
        await asyncio.wait_for(fut, 2)
    except asyncio.TimeoutError:
        print("aw man")


asyncio.run(main())

# > python buggy_timeout.py
# aw man
# hell yeah

@dzhaugasharov Make sure to document it very clearly next to the timeout. ;)