Types exported by dynamic functions may be incorrect

[gvanrossum]

See Jukka's note in #1433 (comment)

After the fix, the exported types aren't correct for generic functions in unannotated code. However, we don't rely on these types anywhere, so I'd suggest merging this PR and creating a new issue for fixing the exported types that refers to this PR.

[AlexWaygood]

Hard to understand what the incorrect behaviour was here without an example — @gvanrossum, is this still an issue?

[gvanrossum]

I have no idea. Let's close this.