Python 3.8 reached end of life (October 2024)

[loreloc]

As suggested by @lkct, upgrade the whole repository to Python 3.9 (EOL Oct 2025) or Python 3.10 (EOL Oct 2026). I guess many things about typing have changed.
https://devguide.python.org/versions/

[lkct]

Ref: https://docs.python.org/3/whatsnew/3.9.html

[loreloc]

Perhaps use this just one time to upgrade all the type hints from Python 3.8 to 3.9.
https://adamj.eu/tech/2021/05/21/python-type-hints-how-to-upgrade-syntax-with-pyupgrade/
https://github.com/asottile/pyupgrade

[lkct]

Just to note that I have left some # FURURE comments in the repo. Those with the corresponding version can be cleaned every time we move to the next Python version.

[loreloc]

We decided to move directly to Python 3.10. Motivation: 3.10 is the default python version in the oldest Ubuntu LTS version. Also, https://colab.google/articles/py3.10

[lkct]

we might need to double-check, e.g. (main as of today)

cirkit/cirkit/templates/region_graph/graph.py

Line 15 in 1d4f8f3

RGNodeMetadata: TypeAlias = dict[str, Union[int, float, str, bool]]

re-opening with lo-pri

EDIT: seems pylint can catch this #244

[loreloc]

That one is now fixed in main, but I do not know if there is an automatic way to check for this kind of issues without reading the whole pylint output.

[loreloc]

I am going to close this, since there is no reliable and automatic way to check that we are always using the latest python features.