New docs for set elements/dictionary keys (Was: Why is dictionary.keys() a list and not a set?)

["Martin v. Löwis"]

Mike Meyer wrote:
> Personally, I think we'd be better off to come up with a term for this
> property that doesn't have a commonly understood meaning that has such
> broad areas of disagreement with the property. I've been using
> "hashable", which I would currently define as "has a __hash__ method
> with the properties described in the __hash__ documentation, or does
> not have either a __cmp__ or a __eq__ method."

I would like to use "hashable" as a term as well, but it appears that
many people would understand that to mean "has a __hash__ 
implementation" (i.e. hash(x) returns a value, instead of raising an
exception).

Regards,
Martin