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Date: Fri, 9 Jan 2015 08:57:03 -0600
Subject: Re: Why does argparse return None instead of [] if an append action isn't used?
From: Skip Montanaro <skip.montanaro@gmail.com>
To: Adam Funk <a24061@ducksburg.com>
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Xref: csiph.com comp.lang.python:83444

> I noticed in use that if an option with the 'append' action isn't
> used, argparse assigns None to it rather than an empty list, &
> confirmed this interactively:

I don't use argparse (or optparse), being a getopt Luddite myself, but
can you set the default for an action in the add_argument call?

Skip