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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Sun, 12 May 2013 17:40:17 -0600
Subject: Re: Differences of "!=" operator behavior in python3 and python2 [ bug? ]
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Xref: csiph.com comp.lang.python:45213

On Sun, May 12, 2013 at 5:23 PM, Mr. Joe <titanix88@gmail.com> wrote:
> I seem to stumble upon a situation where "!=" operator misbehaves in
> python2.x. Not sure if it's my misunderstanding or a bug in python
> implementation. Here's a demo code to reproduce the behavior -

The != operator is implemented by the __ne__ special method.  In
Python 3, the default implementation of __ne__ is to call __eq__ and
return the opposite of whatever it returns.  In Python 2, __ne__ calls
the older __cmp__ method instead, which is no longer meaningful in
Python 3.