Python asyncio Cheat Sheet/Signal readiness with an Event

Wake waiting tasks once a condition becomes true.

Section: Synchronization Primitives

Signal readiness with an Event

python
python
import asyncio

event = asyncio.Event()

async def waiter():
    await event.wait()
    print("event received")

async def setter():
    await asyncio.sleep(0.2)
    event.set()

async def main():
    await asyncio.gather(waiter(), setter())

asyncio.run(main())
Explanation

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