Add rudimentary Pillow stubs

[srittau]

No description provided.

[Akuli]

>>> from PIL import ImageTk
>>> ImageTk
<module 'PIL.ImageTk' from '/tmp/e/lib/python3.8/site-packages/PIL/ImageTk.py'>

But the stub doesn't contain ImageTk.py. Are other submodules missing too? Is this intentional?

[srittau]

Yes, it's very incomplete. (But it has the required __getattr__() in __init__()).

[Akuli]

So in a stub, having __getattr__ in foobar/__init__.py also affects code like from foobar.submodule import thingy, even though that's not how it works at runtime?

[srittau]

I thought it does, but I could be wrong. I will add empty stubs if that's not the case.

[srittau]

I just checked with mypy and the following passes with these stubs:

from PIL.X import Y

reveal_type(Y)  # Revealed type is "Any"

[Akuli]

Are you sure tuple[Foo, Bar] is not affected by the mypy bug?

[srittau]

It's only tuple[X, ...] and tuple (as well as others) in type aliases.

[JelleZijlstra]

Fixed the merge conflict by removing it from the pyright exclude list.

[jakebailey]

Wish I had seen this; I have stubbed out quite a bit of PIL on our stub staging repo: https://github.com/microsoft/python-type-stubs/tree/main/PIL