inspect.signature() raises TypeError for non-comparable callable

[serhiy-storchaka]

Bug report

Example:

class NoncomparableCallable:
    def __call__(self, a):
        pass
    def __eq__(self, other):
        1/0

import inspect
inspect.signature(NoncomparableCallable())

Real world example -- the result of functools.cmp_to_key() (see also #118402).

Linked PRs

• gh-118404: Fix inspect.signature() for non-comparable callables #118405
• [3.12] gh-118404: Fix inspect.signature() for non-comparable callables (GH-118405) #118424