gh-115937: remove extra processing for the __signature__ attribute

[skirpichev]

This is an alternative to #100168.

• Issue: Incorrect description of the __signature__ attribute in docs #115937

[Gouvernathor]

I think this should test that random objects should be passed as-is by the signature function (5, None, []...).
But maybe making this implementation perfect is not urgent as long as a decision has not been made as to what follow-up to bring to the base issue.

[skirpichev]

Since 42407ab there is also type check for returned sig object. So, my commit just returns things to pre-#100168 state (enum module tests kept).

[Gouvernathor]

Ok, this is long-standing behavior, but then it needs to be documented. (again, it can wait)

[erlend-aasland]

Closing in favour of #116086. Thanks for your interest in improving CPython.

[skirpichev]

Thanks for your interest in improving CPython.

Obviously, I'm not very good in this:)

[erlend-aasland]

Obviously, I'm not very good in this:)

I think you've made a lot of very nice contributions, both code contributions, and as a participant in discussions. Sometimes we disagree, and that's ok. It is also often difficult to get a concensus within the core dev group. That's also ok.