Why does argparse return None instead of [] if an append action isn't used?

Mark Lawrence breamoreboy at yahoo.co.uk
Mon Jan 26 18:18:03 CET 2015

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

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