``from shared.linked_list import LinkedListfrom shared.node import Nodedef sum_of_nodes_of_linked_list(l1_: Node, l2_: Node, carry: int = 0):    """    Sum value of nodes    7 -> 1 -> 6 + 5 -> 9 -> 2 = 617+295 = 2 -> 1 -> 9    """    if l1_ is None and l2_ is None and carry == 0:        return    value = carry    if l1_ is not None:        value += l1_.data    if l2_ is not None:        value += l2_.data    # Store the Digit at one    node = Node(value % 10)    if l1_ is not None or l2_ is not None:        more = sum_of_nodes_of_linked_list(l1_.next if l1_ is not None else None,                                           l2_.next if l2_ is not None else None,                                           1 if value >= 10 else 0)        if more is not None:            node.next = more if more is not None else None    return nodedef __collect_node_value(node: Node):    linked_list = LinkedList.create(node)    value = ""    for i in linked_list:        value += str(i.data)    return int(value)if __name__ == "__main__":    l1 = LinkedList()    l1.add(Node(7))    l1.add(Node(1))    l1.add(Node(6))    l2 = LinkedList()    l2.add(Node(5))    l2.add(Node(9))    l2.add(Node(2))    assert __collect_node_value(sum_of_nodes_of_linked_list(l1.node, l2.node)) == 219``