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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Wed, 19 Sep 2012 09:16:23 -0600
Subject: Re: A little morning puzzle
To: Python <python-list@python.org>
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On Wed, Sep 19, 2012 at 6:13 AM, Antoon Pardon
<antoon.pardon@rece.vub.ac.be> wrote:
> On 19-09-12 13:17, Neal Becker wrote:
>> I have a list of dictionaries.  They all have the same keys.  I want to find the
>> set of keys where all the dictionaries have the same values.  Suggestions?
> common_items = reduce(opereator.__and__, [set(dct.iteritems()) for dct
> in lst])
> common_keys = set([item[0] for item in common_items])

You can use dictviews for that:

common_items = reduce(operator.__and__, (d.viewitems() for d in ds))
common_keys = [item[0] for item in common_items]