1、编写用 List 实现的二叉树类 (可参考群中文件，但要编写成类)基本操作包括: 1) 初始化二叉树 2) 判断二叉树是否为空 3)获取根节点4) 获取左子树 5) 获取右子树 6) 设置根节点 7) 设置二叉树左子树 8) 设置二叉树右子树

以下是用 List 实现的二叉树类的代码：

class BinaryTree:
    def __init__(self, root_value=None):
        self.tree = []
        if root_value is not None:
            self.tree.append(root_value)
        else:
            self.tree.append(None)
    
    def is_empty(self):
        return len(self.tree) == 1 and self.tree[0] is None
    
    def get_root(self):
        if self.is_empty():
            raise Exception("Binary tree is empty")
        return self.tree[0]
    
    def get_left_child(self, index):
        left_child_index = index * 2 + 1
        if left_child_index >= len(self.tree) or self.tree[left_child_index] is None:
            return None
        return left_child_index
    
    def get_right_child(self, index):
        right_child_index = index * 2 + 2
        if right_child_index >= len(self.tree) or self.tree[right_child_index] is None:
            return None
        return right_child_index
    
    def set_root(self, value):
        if self.is_empty():
            self.tree.append(value)
        else:
            self.tree[0] = value
    
    def set_left_child(self, index, value):
        left_child_index = index * 2 + 1
        if left_child_index >= len(self.tree):
            self.tree.extend([None] * (left_child_index - len(self.tree) + 1))
        self.tree[left_child_index] = value
    
    def set_right_child(self, index, value):
        right_child_index = index * 2 + 2
        if right_child_index >= len(self.tree):
            self.tree.extend([None] * (right_child_index - len(self.tree) + 1))
        self.tree[right_child_index] = value

使用示例：

# 初始化二叉树
tree = BinaryTree(1)
tree.set_left_child(0, 2)
tree.set_right_child(0, 3)
tree.set_left_child(1, 4)
tree.set_right_child(1, 5)

# 判断二叉树是否为空
print("Is binary tree empty?", tree.is_empty())

# 获取根节点
print("Root node:", tree.get_root())

# 获取左子树和右子树
print("Left child of root node:", tree.get_left_child(0))
print("Right child of root node:", tree.get_right_child(0))

# 设置根节点、左子树和右子树
tree.set_root(6)
tree.set_left_child(0, 7)
tree.set_right_child(2, 8)

# 获取修改后的根节点、左子树和右子树
print("Root node after setting:", tree.get_root())
print("Left child of root node after setting:", tree.get_left_child(0))
print("Right child of root node after setting:", tree.get_right_child(0))