Add type argument to descriptor __get__

[shino16]

This PR makes _call_dispatch use __get__(slf, type(slf)) instead of __get__(slf), working around a CPython segfault (python/cpython#132747).

This will eliminate the segmentation fault mentioned in #2677 (comment). From Python 3.13.3 this workaround will no longer be necessary, but I think we can keep it anyway.

[beverlylytle]

🎉

[Copilot]

Pull Request Overview

This PR addresses a CPython segfault issue (python/cpython#132747) by correctly calling the descriptor protocol's __get__ method with both required arguments. The change ensures that when unbinding builtin methods, the type argument is explicitly passed to __get__.

• Modified the descriptor __get__ call to include the type argument: __get__(slf, type(slf)) instead of __get__(slf)

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[kshitij12345]

Great, thanks @shino16

[riccardofelluga]

Way to go! Great catch!

For info, what changes under the hood when we give the type to the get method?

[shino16]

Thanks! I believe there is no change. The official doc says

If a descriptor is found for a.x, then it is invoked with: desc.__get__(a, type(a)).

A dotted lookup such as super(A, obj).m searches obj.__class__.__mro__ for the base class B immediately following A and then returns B.__dict__['m'].__get__(obj, A). If not a descriptor, m is returned unchanged.

(copied from #2677 (comment))

[shino16]

@KaelanDt This is ready for your review. Thanks!