完成并实现如下链表的基本操作。要求：编写测试函数运行程序，给出结果每个基本操作的运行截图。

以下是链表的基本操作：

1. 初始化链表

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


class LinkedList:
    def __init__(self):
        self.head = None

2. 插入节点

    def insert(self, data):
        new_node = Node(data)

        if self.head is None:
            self.head = new_node
            return

        current_node = self.head

        while current_node.next is not None:
            current_node = current_node.next

        current_node.next = new_node

3. 删除节点

    def delete(self, data):
        if self.head is None:
            return

        if self.head.data == data:
            self.head = self.head.next
            return

        current_node = self.head

        while current_node.next is not None:
            if current_node.next.data == data:
                current_node.next = current_node.next.next
                return
            current_node = current_node.next

4. 查找节点

    def search(self, data):
        current_node = self.head

        while current_node is not None:
            if current_node.data == data:
                return True
            current_node = current_node.next

        return False

5. 打印链表

    def print_list(self):
        current_node = self.head

        while current_node is not None:
            print(current_node.data, end=" -> ")
            current_node = current_node.next

        print("None")

测试代码如下：

linked_list = LinkedList()

linked_list.insert(1)
linked_list.insert(2)
linked_list.insert(3)
linked_list.insert(4)
linked_list.insert(5)

linked_list.print_list()

linked_list.delete(3)

linked_list.print_list()

print(linked_list.search(3))
print(linked_list.search(4))

测试结果截图如下：