def test_zero(self):
self.assertEqual(
subsets([1], 0),
set()
)
def test_two(self):
self.assertEqual(
subsets([1, 2, 3], 2),
set([(1, 2), (1, 3), (2, 3)])
)
def test_three(self):
self.assertEqual(
subsets([1, 2, 3], 3),
set([(1, 2, 3)])
)
def test_single(self):
self.assertEqual(
subsets([1], 1),
set([(1,)])
)