Python 3.12 compatibility

[Archmonger]

Description

Add compatibility for Python 3.12 and some misc code cleanup

• Fix #235

Checklist

Please update this checklist as you complete each item:

• [x] Tests have been developed for bug fixes or new functionality.
• [x] The changelog has been updated, if necessary.
• [x] Documentation has been updated, if necessary.
• [x] GitHub Issues closed by this PR have been linked.

_{By submitting this pull request I agree that all contributions comply with this project's open source license(s).}

[Archmonger]

@rmorshea just a reminder that I still don't have permissions to change required workflows.