bpo-43224: Unpack concrete tuple types into a sequence of types

[serhiy-storchaka]

G[*tuple[int, str]] == G[int, str]

https://bugs.python.org/issue43224

[JelleZijlstra]

I'd rather not do this for the reasons @mrahtz explained elsewhere.

Another point: what about Unpack[Annotated[tuple[int, str], "whatever"]]?

[JelleZijlstra]

I don't think we should do this (see also @mrahtz's comment at #91162 (comment)):

• It would make Unpack[tuple[int, str]] not the same as *tuple[int, str].
• def f(*args: *tuple[int, str]) would end up with int in its __annotations__ because of the way we implemented * there.
• For runtime users of typing, in my experience it's better to keep information around than to simplify. If we simplify, runtime introspection can't reconstruct what the user meant; if we don't simplify, tool authors can probably deal with it easily.

[mrahtz]

+1 to what @JelleZijlstra says.