def test_children():
    node_ex = Node_path([],4,10)
    children = node_ex.children()
    for child in children:
        assert type(node_ex) == type(child)
    return None
def test_childsigs_path():
    node_ex = Node_path([0,1,2,0],4,10)
    children = node_ex.children()
    for child in children:
        assert node_ex.signature == child.signature[:-1]