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From: Lele Gaifax <lele@metapensiero.it>
Subject: Re: checking if two things do not equal None
Date: Sat, 29 Mar 2014 20:24:32 +0100
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Xref: csiph.com comp.lang.python:69340

Steven D'Aprano <steve+comp.lang.python@pearwood.info> writes:

> if not (a is b is None): ...
>
> Or if you prefer:
>
> if a is not b is not None: ...

>>> 1 is not 1 is not None
False

So definitely the former!

ciao, lele.
-- 
nickname: Lele Gaifax | Quando vivrò di quello che ho pensato ieri
real: Emanuele Gaifas | comincerò ad aver paura di chi mi copia.
lele@metapensiero.it  |                 -- Fortunato Depero, 1929.