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From: Wolfgang Maier <wolfgang.maier@biologie.uni-freiburg.de>
Subject: itertools.filterfalse - what is it good for
Date: Fri, 8 Mar 2013 16:45:03 +0000 (UTC)
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Xref: csiph.com comp.lang.python:40868

Dear all,
can anybody point out a situation where you really need itertools.filterfalse() ?
So far, I couldn't think of a case where you couldn't replace it with a
generator expression/if combination.
e.g.,

a=filterfalse(lambda x: x%2, range(1,101))
b=(i for i in range(1,101) if not i % 2)

do not return the same object type, but otherwise are achieving the same thing.
What am I missing here? For sure filterfalse exists for a reason?

Best,
Wolfgang