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))
Returns a set of file lines that contains the intersection of the lines
        within this set and a given set.