PEP218: Representing the empty set

[Andrew McLean]

Looking at PEP218 there is a discussion about the most appropriate way 
of representing the empty set. The two alternatives proposed are {} and 
{-}. I was wondering why either of these is needed. Why not just use 
set()?. It is only two more characters than {-} and a bit more explicit.

Similarly, I find myself initialising dictionaries with dict() rather 
than {}.

Am I missing something?

-- 
Andrew McLean