57 lines
1.2 KiB
Python
57 lines
1.2 KiB
Python
try:
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from collections.abc import MutableSet
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except ImportError:
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from collections import MutableSet
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class SetMixin(MutableSet):
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"""
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Mix-in for sets. You must define __iter__, add, remove
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"""
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def __len__(self):
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length = 0
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for item in self:
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length += 1
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return length
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def __contains__(self, item):
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for has_item in self:
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if item == has_item:
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return True
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return False
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issubset = MutableSet.__le__
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issuperset = MutableSet.__ge__
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union = MutableSet.__or__
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intersection = MutableSet.__and__
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difference = MutableSet.__sub__
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symmetric_difference = MutableSet.__xor__
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def copy(self):
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return set(self)
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def update(self, other):
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self |= other
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def intersection_update(self, other):
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self &= other
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def difference_update(self, other):
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self -= other
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def symmetric_difference_update(self, other):
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self ^= other
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def discard(self, item):
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try:
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self.remove(item)
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except KeyError:
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pass
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@classmethod
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def _from_iterable(cls, it):
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return set(it)
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