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From: Peter Otten <__peter__@web.de>
Newsgroups: comp.lang.python
Subject: Re: Dictionaries and incrementing keys
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Date: Tue, 14 Jun 2011 13:16:47 +0200
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Steve Crook wrote:

> I've always done key creation/incrementation using:
> 
> if key in dict:
>     dict[key] += 1
> else:
>     dict[key] = 1

Your way is usually faster than
 
> dict[key] = dict.get(key, 0) + 1
> 
> Whilst certainly more compact, I'd be interested in views on how
> pythonesque this method is.

You may also consider

http://docs.python.org/library/collections.html#collections.defaultdict
http://docs.python.org/library/collections.html#collections.Counter