Add support for Python 3.12

[hugovk]

The second Python 3.12 release candidate is out! 🚀

Call to action

We strongly encourage maintainers of third-party Python projects to prepare their projects for 3.12 compatibilities during this phase, and where necessary publish Python 3.12 wheels on PyPI to be ready for the final release of 3.12.0.

Python 3.12.0 final is due out in under two weeks: 2023-10-02.

See also https://dev.to/hugovk/help-test-python-312-beta-1508/

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Also remove redundant code for Python 2 including the deprecated compatibility module.

[hugovk]

Python 3.5-3.7 are EOL and no longer receiving security updates (or any updates) from the core Python team.

https://devguide.python.org/versions/

3.5 and 3.6 have also been removed from GitHub Actions: actions/runner-images#8238

I recommend dropping support for 3.5-3.7.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (7a0382e) to head (91e1583).

Additional details and impacted files

@@            Coverage Diff            @@
##            master      #570   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           13        13           
  Lines         1178      1177    -1     
=========================================
- Hits          1178      1177    -1     

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[hugovk]

Merge conflict resolved!

Since I opened this, 3.12 support has instead been added in #574 🎉

I think there's still some useful bits in here, but feel free to close. 👍

[hugovk]

Python 3.13 is out next week, but closing this year old PR due to lack of interest.