* Add python_requires to help pip
* Update supported versions in tox.ini
* Upgrade Python syntax with pyupgrade --py37-plus
* Bump GitHub Actions
* Add Python 3.11 and 3.12 to CI
* Remove six dependency
* Remove redundant dependencies
* Remove redudant Python 3.5 code
* Drop support for EOL Python 3.7
* Upgrade Python syntax with pyupgrade --py38-plus
* Update CHANGELOG
* More f-strings
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Co-authored-by: Hugo van Kemenade <hugovk@users.noreply.github.com>
* Linting of OAuth2 mod. + update tests to detect core package path
* Tweak imports in tests + update tox ini to ignore Flake8 E501 error
* Tweak tox ini - ignore examples
* Remove `f`-string from OAuth2 mod.
* More import tweaks in core package + tests
* Update flake8 config. in tox ini - set line length limit to 99 chars.
