def test_many(self):
tree = BinaryNode.parse_tree("[[1[[5]3[4]]]5[6[11]]]", int)
sol = solution(tree, 10)
self.assertEqual(10, sol[0].value + sol[1].value)
def test_no_sol(self):
tree = BinaryNode.parse_tree("[[1[[5]3[4]]]5[6[12]]]", int)
sol = solution(tree, 12)
self.assertIsNone(sol)
