def test_symmetric_point_on_edge(self):
grid = Grid(9)
expected = (9, 1)
actual = grid.symmetric_point(1, 9)
self.assertEqual(expected, actual)
def test_bad_symmetric_point(self):
grid = Grid(9)
actual = grid.symmetric_point(-3, 45)
self.assertIsNone(actual)
def test_symmetric_point(self):
grid = Grid(9)
expected = (8, 5)
actual = grid.symmetric_point(2, 5)
self.assertEqual(expected, actual)
