Python 3.7+Async programmingfunction

asyncio.create_task()

tasks

Wraps a coroutine in a Task and schedules it on the event loop: it starts at the current coroutine's next await, and you need not await its result right away.

Syntax

task = asyncio.create_task(coro())

Nothing runs at the call site itself: the task is queued on the event loop and only starts once the current coroutine reaches its next await. Also keep a reference — the loop holds only a weak one, so a task assigned nowhere can be garbage-collected mid-flight; park it in a variable or a set until it finishes. An exception raised inside a task stays silent until someone awaits it, which is how fire-and-forget tasks swallow bugs.

Examples

import asyncio
async def bg():
    await asyncio.sleep(0)
    return 'done'
async def main():
    t = asyncio.create_task(bg())
    print('working...')  # → working... — задача запланирована, но ещё не начала выполняться
    result = await t
    print(result)  # → done
asyncio.run(main())

See also

Common errors

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