def test_true_2(self):
     self.assertTrue(is_isogram('isogram'))
 def test_true(self):
     self.assertTrue(is_isogram('Dermatoglyphics'))
 def test_false_3(self):
     self.assertFalse(is_isogram('isIsogram'))
 def test_false_2(self):
     self.assertFalse(is_isogram('moOse'))
 def test_false(self):
     self.assertFalse(is_isogram('aba'))
 def test_true_3(self):
     self.assertTrue(is_isogram(''))