Functional way to compare things inside a list

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Date	Thu, 20 Sep 2012 18:58:21 -0400 (EDT)
Subject	Functional way to compare things inside a list
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Hi,

list = [{'1': []}, {'2': []}, {'3': ['4', '5']}]

I want to check for a value (e.g. '4'), and get the key of the dictionary
that contains that value.
(Yep, this is bizarre.)

some_magic(list, '4')
=> '3'

What's the functional way to do it?
Is it possible to do it with a one-liner?

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Functional way to compare things inside a list thorsopia@lavabit.com - 2012-09-20 18:58 -0400
  Re: Functional way to compare things inside a list "Ivan@work" <ivan.cvetkovic@pakel.hr> - 2012-09-21 10:24 +0200
  Re: Functional way to compare things inside a list Alexander Blinne <news@blinne.net> - 2012-09-21 10:31 +0200
  Re: Functional way to compare things inside a list Ulrich Eckhardt <ulrich.eckhardt@dominolaser.com> - 2012-09-21 10:52 +0200
    Re: Functional way to compare things inside a list 88888 Dihedral <dihedral88888@googlemail.com> - 2012-09-21 12:54 -0700
      Re: Functional way to compare things inside a list Ian Kelly <ian.g.kelly@gmail.com> - 2012-09-21 14:49 -0600
        Re: Functional way to compare things inside a list 88888 Dihedral <dihedral88888@googlemail.com> - 2012-09-21 14:45 -0700
        Re: Functional way to compare things inside a list 88888 Dihedral <dihedral88888@googlemail.com> - 2012-09-21 14:45 -0700
        Re: Functional way to compare things inside a list Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-09-22 01:25 +0000
          Re: Functional way to compare things inside a list Ian Kelly <ian.g.kelly@gmail.com> - 2012-09-22 00:22 -0600
            Re: Functional way to compare things inside a list 88888 Dihedral <dihedral88888@googlemail.com> - 2012-09-21 23:50 -0700
            Re: Functional way to compare things inside a list 88888 Dihedral <dihedral88888@googlemail.com> - 2012-09-21 23:50 -0700
          Re: Functional way to compare things inside a list Jamie Paul Griffin <jamie@kode5.net> - 2012-09-22 08:08 +0100
          Re: Functional way to compare things inside a list Andrew Berg <bahamutzero8825@gmail.com> - 2012-09-22 02:19 -0500
            Re: Functional way to compare things inside a list Ramchandra Apte <maniandram01@gmail.com> - 2012-09-22 21:09 -0700
            Re: Functional way to compare things inside a list Ramchandra Apte <maniandram01@gmail.com> - 2012-09-22 21:09 -0700

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