New submission from Maytag Metalark:
Performing a logical negation (`not`) on `NotImplemented` should return
`NotImplemented`. Currently, it returns `False`.
A common pattern for implementing __eq__ and __ne__ is to implement the
comparison in __eq__, and simply delegate to it in __ne__ with
R. David Murray added the comment:
This would break Python's consistency. 'not' of a value returns its boolean
inverse, and the boolean value of NotImplemented is True, just like the boolean
value of any object that does not have methods that set its boolean value is
True. Having anything
