I disagree with `Optional`. It can cause confusion in function signatures, since an argument typed as "optional" might still be required if there is no default value. Basically I think the name is bad, it should be `Nullable` or something.

I believe Python's own documentation also recommends the shorthand syntax over `Union`. Linters like Pylint and Ruff also warn if you use the imported `Union`/`Optional` types. The latter even auto-fixes it for you by switching to the shorthand syntax.