FWIW, it seems to me (author of `cached_property` patch) that while just using `@property` on the abstract method plus a comment is a reasonable and functional workaround that sacrifices only a small documentation value, there's no reason why `@cached_property` shouldn't propagate this flag in the same way `@property` does. It seems reasonable to me to consider this behavior discrepancy a bug; I'd have fixed it if made aware of it while developing `cached_property`.