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From: Peter Otten <__peter__@web.de>
Subject: Re: Argument Presence Checking via Identity or Boolean Operation?
Date: Thu, 04 Jun 2015 11:28:45 +0200
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Xref: csiph.com comp.lang.python:92041

Frank Millman wrote:

> I have a slight variation in that I want to keep a reference to the
> argument -
> 
> def __init__(self, arg=None):
>     self.arg = arg or []
> 
> Based on your comment, I have changed it to -
> 
> def __init__(self, arg=None):
>     self.arg = [] if arg is None else arg
> 
> Does this pass your 'stop and consider' test?

Yes, that avoids the problem of the original code.