Add another example to the collections module docs.
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@ -783,6 +783,9 @@ semantics pass-in keyword arguments using a regular unordered dictionary.
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`Equivalent OrderedDict recipe <http://code.activestate.com/recipes/576693/>`_
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that runs on Python 2.4 or later.
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:class:`OrderedDict` Examples and Recipes
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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Since an ordered dictionary remembers its insertion order, it can be used
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in conjuction with sorting to make a sorted dictionary::
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@ -812,11 +815,28 @@ original insertion position is changed and moved to the end::
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class LastUpdatedOrderedDict(OrderedDict):
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'Store items in the order the keys were last added'
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def __setitem__(self, key, value):
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if key in self:
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del self[key]
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OrderedDict.__setitem__(self, key, value)
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An ordered dictionary can combined with the :class:`Counter` class
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so that the counter remembers the order elements are first encountered::
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class OrderedCounter(Counter, OrderedDict):
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'Counter that remembers the order elements are first encountered'
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def __init__(self, iterable=None, **kwds):
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OrderedDict.__init__(self)
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Counter.__init__(self, iterable, **kwds)
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def __repr__(self):
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return '%s(%r)' % (self.__class__.__name__, OrderedDict(self))
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def __reduce__(self):
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return self.__class__, (OrderedDict(self),)
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:class:`UserDict` objects
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-------------------------
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