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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def difference_update(self, other):
 """Update the set, removing any elements from other which are in the set. @param other: the collection of items with which to update the set @type other: Set object """

        if not isinstance(other, Set):
            raise ValueError('other must be a Set instance')
        if self is other:
            self.items = []
        else:
            for item in other.items:
                self.discard(item)