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Date: Fri, 24 Feb 2012 08:53:49 +1100
Subject: Re: sum() requires number, not simply __add__
From: Chris Angelico <rosuav@gmail.com>
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:20755

On Fri, Feb 24, 2012 at 8:41 AM, Arnaud Delobelle <arnodel@gmail.com> wrote=
:
> _sentinel =3D object()
>
> def sum(iterable, start=3D_sentinel):
> =A0 =A0if start is _sentinel:
>
> del _sentinel

Somewhat off-topic: Doesn't the if statement there do a lookup for a
global, which would mean that 'del _sentinel' will cause it to fail?
Or have I missed something here?

ChrisA