Hm, I actually like the original proposal better. Perhaps collections.abc.Mapping is more common than typing.Mapping, but is it more common *in function annotations*? I don't think so.

Also, I like showing e.g. Iterator[Tuple[int, Any]] rather than just Iterator. This is documentation we're talking about, and the parameter types are very useful as documentation. (However, abbreviating List[Any] as List is fine, since they mean the same thing.)