> Maybe the methods could all rely on `get_names` that
> return `dir(self.__class__)`,

Please read the previous posts on the subject.  The only reason to do this is if we want the module to explicitly support attaching methods directly to instances.  That practice has disadvantages (no access to self) and it is at odds with the design of the module (nothing we ever intended to explicitly support) and it is outside of usual Python norms (methods attached to classes).  AFAICT, the OP's need could be met using traditional (and supported) techniques such as class composition.  Accordingly, there isn't any need to go down this more unusual path.