support cached_property #8913
Description
The functools.cached_property decorator doesn't get typechecked correctly:
from functools import cached_property
class Superclass:
@property
def prop(self) -> int:
...
class Subclass(Superclass):
@cached_property
def prop(self) -> int:
... mypy (version 0.770) reports:
error: Signature of "prop" incompatible with supertype "Superclass"