def test_cyclic_find(self):
node1, node2 = Node(), Node()
node1.children.append(node2)
node2.children.append(node1)
assert node1.find_root() == None
assert node2.find_root() == None
def test_find_root(self):
node1, node1a, node1b, node1a1 = Node(), Node(), Node(), Node()
node1.children.append(node1a, node1b)
node1a.children.append(node1a1)
assert node1.find_root() == None
assert node1a.find_root() == node1
assert node1b.find_root() == node1
assert node1a1.find_root() == node1
