The first question is do we ever want to update the required Python version?

If so, then we need to agree on what the (possible) criteria are. The actual
decision is likely to be a judgment call after looking over the criteria.

The current reasons to update are:
3.11 has StrEnum. We have our own implementation of StrEnum, so this would be a
nice to have.
3.11 also has @typing.overload, which would be useful for Node factory
functions (SutConfig|TGConfig -> SutNode|TGNode). Provided by
typing_extensions, changed in 4.2.0.
3.12 has @typing.override (useful for docs), but we can get that with the
typing_extensions module (version 4.4.0, but changed in 4.5.0). Tt doesn't work
with Pylama though due to a bug: https://github.com/klen/pylama/pull/247, but
that is not a big deal since we should move away from Pylama since it's not
maintained anymore (or seems not to be).