Add a dict view usage example.
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@ -1906,6 +1906,36 @@ to another dictionary view or a set):
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four operations will fail if an involved dictionary contains such a value.
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four operations will fail if an involved dictionary contains such a value.
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An example of dictionary view usage::
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>>> dishes = {'eggs': 2, 'sausage': 1, 'bacon': 1, 'spam': 500}
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>>> keys = dishes.keys()
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>>> values = dishes.values()
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>>> # iteration
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>>> n = 0
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>>> for val in values:
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... n += val
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>>> print(n)
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504
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>>> # keys and values are iterated over in the same order
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>>> list(keys)
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['eggs', 'bacon', 'sausage', 'spam']
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>>> list(values)
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[2, 1, 1, 500]
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>>> # view objects are dynamic and reflect dict changes
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>>> del dishes['eggs']
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>>> del dishes['sausage']
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>>> list(keys)
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['spam', 'bacon']
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>>> # set operations
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>>> keys & {'eggs', 'bacon', 'salad'}
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{'eggs', 'bacon'}
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.. _bltin-file-objects:
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.. _bltin-file-objects:
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File Objects
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File Objects
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