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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 add_intersecting(self, division, intersection=None, symm=True):
 """ Adds paired relationships between intersecting divisions. Optional intersection represents the portion of the area of the related division intersecting this division. You can only specify an intersection on one side of the relationship when adding a peer. """

        relationship, created = IntersectRelationship.objects.update_or_create(
            from_division=self,
            to_division=division,
            defaults={"intersection": intersection},
        )
        if symm:
            division.add_intersecting(self, None, False)
        return relationship