2．请编程实现一个对单链表进行基本操作的系统，主要包括表的创建、输入、查询、取值、插入、删除和输出等操作。（要求：可以采用带头结点和不带头结点的单链表）

以下是使用带头结点实现的单链表基本操作系统：

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

class LinkedList:
    def __init__(self):
        self.head = Node()

    def append(self, data):
        new_node = Node(data)
        current = self.head
        while current.next != None:
            current = current.next
        current.next = new_node

    def length(self):
        current = self.head
        total = 0
        while current.next != None:
            total += 1
            current = current.next
        return total

    def display(self):
        elements = []
        current = self.head
        while current.next != None:
            current = current.next
            elements.append(current.data)
        print(elements)

    def get(self, index):
        if index >= self.length():
            print("Error: 'Get' Index out of range!")
            return None
        current_idx = 0
        current_node = self.head
        while True:
            current_node = current_node.next
            if current_idx == index: return current_node.data
            current_idx += 1

    def delete(self, index):
        if index >= self.length():
            print("Error: 'Delete' Index out of range!")
            return
        current_idx = 0
        current_node = self.head
        while True:
            last_node = current_node
            current_node = current_node.next
            if current_idx == index:
                last_node.next = current_node.next
                return
            current_idx += 1

    def insert(self, index, data):
        if index >= self.length():
            print("Error: 'Insert' Index out of range!")
            return
        current_idx = 0
        current_node = self.head
        while True:
            last_node = current_node
            current_node = current_node.next
            if current_idx == index:
                new_node = Node(data)
                last_node.next = new_node
                new_node.next = current_node
                return
            current_idx += 1

使用示例：

# 创建一个带头结点的单链表
my_list = LinkedList()

# 在链表尾部追加元素
my_list.append(1)
my_list.append(2)
my_list.append(3)

# 输出链表元素
my_list.display()  # [1, 2, 3]

# 查询元素
print(my_list.get(1))  # 2

# 删除元素
my_list.delete(1)
my_list.display()  # [1, 3]

# 在指定位置插入元素
my_list.insert(1, 2)
my_list.display()  # [1, 2, 3]