def test_xm(self): self.assertFalse(subtractive_combination_validity((("XM", 0), )))
def test_cm(self): self.assertTrue(subtractive_combination_validity((("CM", 0), )))
def test_xm(self): self.assertFalse(subtractive_combination_validity((("XM", 0), )))
def test_cm(self): self.assertTrue(subtractive_combination_validity((("CM", 0), )))