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From: Mark Lawrence <breamoreboy@yahoo.co.uk>
Subject: Re: Why does argparse return None instead of [] if an append action isn't used?
Date: Mon, 26 Jan 2015 17:18:03 +0000
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On 26/01/2015 16:29, Jussi Piitulainen wrote:
>
> I've used tuples to convey the intention of immutability, as opposed
> to using lists. For all I know, collecting a generator (from groupby)
> into a tuple might be slower than collecting it into a list. I have no
> intention to measure this. The programs have been fast enough for me.
>

IIRC, and probably from this list, creating tuples is way faster than 
creating lists, but accessing items is slower.  Can anybody confirm this 
for us?

-- 
My fellow Pythonistas, ask not what our language can do for you, ask
what you can do for our language.

Mark Lawrence