3) extend the __slots__ handler to set the descriptor's doc string
to dictionary values if the slot's value is a dictionary.
I haven't implemented this, because I don't know a thing about Python's C interface. If someone more able would knock off a prototype, I would be grateful.
If I understand this proposal correctly (the dict values would provide the docstrings for the slots) I'd rather not make this default behavior; different metaclasses may want to use the dict value for different purposes, and subsuming it by default for the doc string would make that harder to do.
--Guido van Rossum (home page: http://www.python.org/%7Eguido/)