Add third-party library pyqtgraph

[TiborVoelcker]

Resolves #14881.

[TiborVoelcker]

These are mainly the auto-generated stub files for now, with only the dynamically inherited methods (mentioned in #14882) fixed that I found.

I would be happy to put in some more work if the PR is wanted.

[github-actions]

According to mypy_primer, this change has no effect on the checked open source code. 🤖🎉

[brianschubert]

Marking this as a draft for now since the CI isn't passing.

If there are many issues with the auto-generated stubs, you can consider reducing to a smaller set of partial stubs that you are able to get CI passing for. See also the below links for tips on writing partial stubs:

• https://typing.python.org/en/latest/guides/writing_stubs.html#incomplete-stubs
• https://typing.python.org/en/latest/spec/distributing.html#partial-stub-packages
• https://github.com/python/typeshed/blob/6b222ca89d993429f63639589de43a4c34fca293/CONTRIBUTING.md#the-metadatatoml-file

[TiborVoelcker]

I was waiting to see if such a MR would welcomed.
Sadly, now I don't have the time for this anymore. But I'm planning to complete this (at least partial stubs as you suggested) once I have some time available again.

[srittau]

We generally accept stubs for actively maintained packages published on PyPI that don't have their own stub or inline annotations.