Finds the 2 depot positions on the outside

def corner_depots(self) -> Set[Point2]:
        """ Finds the 2 depot positions on the outside """
        if len(self.upper2_for_ramp_wall) == 2:
            points = self.upper2_for_ramp_wall
            p1 = points.pop().offset((self.x_offset, self.y_offset))  # still an error with pixelmap?
            p2 = points.pop().offset((self.x_offset, self.y_offset))
            center = p1.towards(p2, p1.distance_to(p2) / 2)
            depotPosition = self.depot_in_middle
            # Offset from middle depot to corner depots is (2, 1)
            intersects = center.circle_intersection(depotPosition, 5 ** 0.5)
            return intersects
        raise Exception("Not implemented. Trying to access a ramp that has a wrong amount of upper points.")