Hi, I'm cross posting this for visibility. I've recently proposed PEP 718 (https://pep-previews--3179.org.readthedocs.build/pep-0718/) which allows for subscripting function, method and builtin functions/methods at runtime. I didn't imagine it'd require massive changes to type checkers but I thought it'd be nice to let everyone know about this (unless I'm being very naive). Thanks, James H-B.