Message 313522 - Python tracker

Marking this as a documentation enhancement request for now, but I think we should also consider changing the type creation behaviour in 3.8 to implicitly add __int__ and __trunc__ definitions when __index__ is defined, but they aren't.

That way, no behaviour will change for classes that explicitly define __int__ or __trunc__, but classes that only define __index__ without defining the other methods will behave more intuitively.