如何通过递归在链表中添加元素？

class Node:
    def __init__(self, data):
        self.data = data
        self.next = None

def add_element(head, element):
    if head is None:
        return Node(element)
    else:
        head.next = add_element(head.next, element)
        return head

class Node:
    def __init__(self, data):
        self.data = data
        self.next = None

def add_element(head, element):
    if head is None:
        return Node(element)
    else:
        head.next = add_element(head.next, element)
        return head

def print_list(head):
    current = head
    while current:
        print(current.data, end=" ")
        current = current.next
    print()

# 创建一个链表
head = Node(1)
head.next = Node(2)
head.next.next = Node(3)

# 在链表中添加元素
head = add_element(head, 4)
head = add_element(head, 5)

# 打印链表
print_list(head)