def test_three_items(self):
items = ['a', 'b', 'c']
self.assertEqual(
list(permutations(items)),
[
('a', 'b', 'c'), ('a', 'c', 'b'), ('b', 'a', 'c'),
('b', 'c', 'a'), ('c', 'a', 'b'), ('c', 'b', 'a')
]
)
def test_one_item(self):
self.assertEqual(list(permutations(['a'])), [('a',)])
def test_zero_items(self):
self.assertEqual(list(permutations([])), [])