Check typing instead of string matching

[ljos]

Hi--I am trying to get this working on python3.14 and there has been some changes to the type system so the string checks that were there does not work anymore. I updated the code to look at the types instead.

This was preventing me from even importing the library.

(I am now getting a segfault when I try to create a relation, so you might see some more PRs from me).

[awdemos]

Thanks for working on Python 3.14 compatibility — this kind of modernization is welcome.

I reviewed the diff and have a few concerns before I can approve:

• Backward compatibility: typing.TypeAlias and types.NoneType are not available in Python 3.8/3.9, which the project still claims to support (Python 3.7+). Could you guard these or use type(None) and a conditional import?
• get_type_hints(..., include_extras=True) requires Python 3.9+. If the minimum supported version is still 3.7, this will break.
• The PR mixes functional changes with a lot of formatting-only changes. Splitting the style cleanup into a separate PR would make review much easier.
• Could you add a test or a CI matrix entry that exercises this on 3.14 (or at least on the lowest supported version) so we don’t regress?

I like the direction, but I’d like to see the compatibility story tightened before approving.