Add support for Python 3.13

[hugovk]

Helps https://github.com/samuelcolvin/watchfiles/issues/276.

Temporarily use PYO3_USE_ABI3_FORWARD_COMPATIBILITY: 1 until PyO3 supports Python 3.13.

Hopefully there will be a PyO3 0.21.3 soon so we can remove it:

https://github.com/PyO3/pyo3/issues/4038#issuecomment-2110007551

[EwoutH]

PyO3 0.22.0 and 0.22.1 are released with Python 3.13 support.

[EwoutH]

Opened a PR to update PyO3 to 0.22.1: https://github.com/samuelcolvin/watchfiles/pull/286

[hugovk]

The Python 3.13 release candidate is out now! :rocket:

We strongly encourage maintainers of third-party Python projects to prepare their projects for 3.13 compatibilities during this phase, and where necessary publish Python 3.13 wheels on PyPI to be ready for the final release of 3.13.0. Any binary wheels built against Python 3.13.0rc1 will work with future versions of Python 3.13. As always, report any issues to the Python bug tracker.

https://discuss.python.org/t/python-3-13-0-release-candidate-1-released/59703

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 99.51%. Comparing base (9f19a18) to head (1b36337). Report is 11 commits behind head on main.

Additional details and impacted files

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[EwoutH]

@hugovk could you rebase this PR now that #287 is merged?

[hugovk]

Rebased!

[samuelcolvin]

Thanks so much.

@hugovk, since you're "here": thanks so much for Top PyPI Packages, it's really useful :pray:. Please could you update it for August.

[hugovk]

You're welcome!

Yeah, I need to sort out August, it's automated and failed to run on the 1st because it exceeded BigQuery quota. It (should be) using a dedicated key, so I'll probably need to reduce the total from 8k back towards the original 5k.

[hugovk]

PS thanks for watchfiles, it's a dependency of sphinx-autobuild which makes it much easier to work on Python docs. We have it enabled for CPython docs, the PEPs and devguide.