def test_overly_long_slice(self):
     with self.assertRaises(ValueError):
         slices("012", 4)
 def test_overly_long_slice(self):
     with self.assertRaises(ValueError):
         slices("012", 4)
 def test_slices_of_two(self):
     self.assertEqual([[9, 7], [7, 8], [8, 6], [6, 7],
                       [7, 5], [5, 6], [6, 4]],
                      slices("97867564", 2))
 def test_slices_of_two(self):
     self.assertEqual(
         [[9, 7], [7, 8], [8, 6], [6, 7], [7, 5], [5, 6], [6, 4]],
         slices("97867564", 2))