To add some more context, the existing Python documentation is a little misleading in this situation:

https://docs.python.org/3/library/abc.html#abc.abstractmethod

It shows that labeling a method with

@property
@abstractmethod

ought to be done in the order above, but this ordering currently breaks the abstract method check if you swap our @property for @cached_property. The documentation also says

"In order to correctly interoperate with the abstract base class machinery, the descriptor must identify itself as abstract using __isabstractmethod__." which @cached_property does not do, but as the documentation then shows, @property does do this properly.