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)
