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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 intersection(self, other: 'FileLineSet') -> 'FileLineSet': """ Returns a set of file lines that contains the intersection of the lines within this set and a given set. """

        assert isinstance(other, FileLineSet)
        set_self = set(self)
        set_other = set(other)
        set_union = set_self & set_other
        return FileLineSet.from_list(list(set_union))