Hello!

In https://github.com/python/cpython/blob/master/Lib/typing.py#L115-L117, there is a note about the io and re classes not being included in typing.__all__.  I am a relatively new user of typing, and I did `from typing import *` in my code.  I ran the code through mypy first, which reported no problems, but then running Python 3.6 failed with a NameError (name 'IO' is not defined).

Reading through the typing source, it's clear that this was an intentional decision.  So, instead of reporting a bug, I'd like to request a documentation enhancement!

The docs for typing make no mention of typing.io or typing.re.  So, my request is: In the sections for the IO/TextIO/BinaryIO and Pattern/Match classes, include text warning the user that these types are not imported when you do `from typing import *`.

> So, my request is: In the sections for the IO/TextIO/BinaryIO and Pattern/Match classes, include text warning the user that these types are not imported when you do `from typing import *`.

I don't think this should really be a warning, probably just a note, but otherwise I totally agree. Would you like to make a PR?

Shadowing the real modules `re` and `io` by

   from typing import *

would indeed be bad, but that argument IMHO doesn't hold for the types `IO`, `TextIO` and `BinaryIO`, yet they are not listed in `typing.__all__`. Is there a reason for that? And if not, could `IO`, `TextIO` and `BinaryIO` be added to `typing.__all__`?

Wait, is the OP maybe that there’s a difference between typeshed an the stdlib typing.py?

It turns out that IO, TextIO, BinaryIO, Match, and Pattern aren't in typing.__all__. As Walter points out above, there's no clear reason for this. I am submitting a PR to add them to __all__.

New changeset e1bcc88a502aa0239b6bcc4da3fe024307fd27f4 by Miss Islington (bot) in branch '3.10':
bpo-38352: Add to typing.__all__ (GH-25821) (#25884)
https://github.com/python/cpython/commit/e1bcc88a502aa0239b6bcc4da3fe024307fd27f4

New changeset 00726e51ade10c7e3535811eb700418725244230 by Miss Islington (bot) in branch '3.9':
bpo-38352: Add to typing.__all__ (GH-25821) (#25885)
https://github.com/python/cpython/commit/00726e51ade10c7e3535811eb700418725244230

Fix merged to main (3.11), 3.10, and 3.9. Not applicable to older Pythons as they are security fixes only.

@Łukasz thanks for your merging spree!

I'm actually not sure this should go into 3.9. Seems potentially dangerous that people upgrading from an earlier 3.9 patch release will now see new names injected into their namespace if they do `from typing import *`.