Add __all__ for asyncio.unix_events & asyncio.taskgroups, and simplify asyncio.__init__

[AlexWaygood]

Now that all asyncio submodules have accurate __all__s, we can drastically simplify the imports in asyncio.__init__.pyi and do something much more similar to what's done at runtime.

[AlexWaygood]

@rchen152, any idea what the pytype error is trying to tell me? 🙂

[rchen152]

Looks like pytype is either not allowing __all__ to be imported multiple times or complaining about it being defined multiple times in the same file (despite the version guards). Either way, looks like a pytype bug to me =/ Investigating.

[AlexWaygood]

Investigating.

Thank you!!

[rchen152]

I've submitted a fix for this; as long as I don't run into any unexpected problems, I should be able to cut a pytype release containing the fix tomorrow or Thursday.

[rchen152]

Alright, pytype-2022.2.23 is out. Let me know if you run into any problems.

[AlexWaygood]

Alright, pytype-2022.2.23 is out. Let me know if you run into any problems.

Looks like it's working great — thanks for the quick fix!

[github-actions]

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

core (https://github.com/home-assistant/core)
+ homeassistant/runner.py:51: error: Unused "type: ignore[misc, valid-type]" comment
+ homeassistant/runner.py:62: error: "HassEventLoopPolicy" has no attribute "_loop_factory"  [attr-defined]

[AlexWaygood]

Ping on this -- the CI is green now that the pytype version used in CI has been updated :)

[srittau]

While I'm a tad worried about the second line in the primer output, this can be sorted out later if necessary.