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From: Nobody <nobody@nowhere.com>
Subject: Re: Eval of expr with 'or' and 'and' within
Date: Sat, 15 Jun 2013 00:06:41 +0100
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On Fri, 14 Jun 2013 16:49:11 +0000, Steven D'Aprano wrote:

> Unlike Javascript though, Python's idea of truthy and falsey is actually 
> quite consistent:

Beyond that, if a user-defined type implements a __nonzero__() method then
it determines whether an instance is true or false. If it implements a
__len__() method, then an instance is true if it has a non-zero length.