asyncio: updates for 3.11

[JelleZijlstra]

CPython changes:

• python/cpython@13c10bf
• python/cpython@9523c0d
• python/cpython@9f04ee5
• python/cpython@d03acd7
• python/cpython@195a46d

[hauntsaninja]

If we merge #7845 first we'll know whether this got everything ;-)

[JelleZijlstra]

I have a couple more things to fix tomorrow.

The mypy-primer hit is a true positive: asyncio.run only accepts coroutines, not arbitrary awaitables, and that's been true as far back as 3.7.

[AlexWaygood]

Looks good! I read through the whole thing and compared with the runtime. Just a few small questions/comments.

[AlexWaygood]

Should we create an alias somewhere (_typeshed?) for Coroutine[Any, Any, _T] | Generator[Any, None, _T]? I think we could use it quite a lot in our asyncio stubs. (No need to do that in this PR.)

[JelleZijlstra]

It's probably worth checking whether we still need the Generator variant. That feels like a holdover from the pre-await days.

[github-actions]

Diff from mypy_primer, showing the effect of this PR on open source code:

boostedblob (https://github.com/hauntsaninja/boostedblob)
+ boostedblob/cli.py:29: error: Argument 1 to "run" has incompatible type "Awaitable[T]"; expected "Coroutine[Any, Any, <nothing>]"