sp_x, sp_y = sympy.symbols('x y')
self.assertEqual(self.square.tosympy(),
sympy.And(-sp_x + 1 >= 0, -sp_y + 1 >= 0, sp_x >= 0, sp_y >= 0))
sp_x, sp_y = sympy.symbols('x y')
self.assertEqual(self.square.tosympy(),
sympy.And(-sp_x + 1 >= 0, -sp_y + 1 >= 0, sp_x >= 0, sp_y >= 0))