[Python-Dev] Add PyType_GetSlot

["Martin v. Löwis"]

I'd like to resolve a long-standing issue of the stable ABI in 3.4:

http://bugs.python.org/issue17162

The issue is that, since PyTypeObject is opaque, module authors cannot
get at tp_free, which they may need to in order to implement tp_dealloc
properly.

Rather than providing the proposed specific wrapper for tp_dealloc, I
propose to add a generic PyType_GetSlot function. From a stability point
of view, exposing slot values is uncritical - it's just that the layout
of the type object is hidden.

Any objection to adding this before RC1?

Regards,
Martin