def test_from_data2(self):
test = Chain.from_data([1, 2, 1, 1], 2)
check = Chain({(1, 2): {1: 1}, (2, 1): {1: 1}, (1, 1): {None: 1}})
self.assertEqual(test, check)
def test_from_data1(self):
test = Chain.from_data([1, 2, 1, 1])
check = Chain({(1,): {1: 1, 2: 1, None: 1}, (2,): {1: 1}})
self.assertEqual(test, check)