def test_two_unique_vals(self): self.assertEqual(isUnique("ab"), True)
def test_single_val(self): self.assertEqual(isUnique("a"), True)
def test_four_non_unique_vals(self): self.assertEqual(isUnique("fata"), False)
def test_four_unique_vals(self): self.assertEqual(isUnique("czq"), True)
def test_three_non_unique_vals(self): self.assertEqual(isUnique("aba"), False)
def test_three_unique_vals(self): self.assertEqual(isUnique("abc"), True)