def test_comparisons(self): c1 = Composition({"S": 1}) c1_1 = Composition({"S": 1.00000000000001}) c2 = Composition({"S": 2}) c3 = Composition({"O": 1}) c4 = Composition({"O": 1, "S": 1}) self.assertFalse(c1 > c2) self.assertFalse(c1_1 > c1) self.assertFalse(c1_1 < c1) self.assertTrue(c1 > c3) self.assertTrue(c3 < c1) self.assertTrue(c4 > c1) self.assertEqual(sorted([c1, c1_1, c2, c4, c3]), [c3, c1, c1_1, c4, c2]) foo = Element("Fe") self.assertEqual(c1.__eq__(foo), NotImplemented) self.assertEqual(c1.__ne__(foo), NotImplemented) self.assertEqual(c1.__lt__(foo), NotImplemented)