29 lines
604 B
Python
29 lines
604 B
Python
"""
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>>> import weakref
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>>> stock = weakref.WeakValueDictionary()
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>>> catalog = [Cheese('Red Leicester'), Cheese('Tilsit'),
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... Cheese('Brie'), Cheese('Parmesan')]
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...
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>>> for cheese in catalog:
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... stock[cheese.kind] = cheese
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...
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>>> sorted(stock.keys())
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['Brie', 'Parmesan', 'Red Leicester', 'Tilsit']
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>>> del catalog
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>>> sorted(stock.keys())
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['Parmesan']
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>>> del cheese
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>>> sorted(stock.keys())
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[]
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"""
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# tag::CHEESE_CLASS[]
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class Cheese:
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def __init__(self, kind):
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self.kind = kind
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def __repr__(self):
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return 'Cheese(%r)' % self.kind
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# end::CHEESE_CLASS[]
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