class Node:
   def __init__(self,my_data):
      self.prev = None
      self.data = my_data
      self.next = None
class double_list:
   def __init__(self):
      self.head = None
      self.tail = None
   def add_data(self,my_data):
      new_node = Node(my_data)
      if(self.head == None):
         self.head = self.tail = new_node
         self.head.previous = None
         self.tail.next = None
      else:
         self.tail.next = new_node
         new_node.previous = self.tail
         self.tail = new_node
         self.tail.next = None
   def min_node(self):
      curr = self.head
      if(self.head == None):
         print("列表为空")
         return 0
      else:
         min = self.head.data
         while(curr != None):
            if(min > curr.data):
               min = curr.data
            curr = curr.next
         return min
   def max_node(self):
      curr = self.head
      if(self.head == None):
         print("列表为空")
         return 0
      else:
         max = self.head.data
         while(curr != None):
            if(curr.data > max):
               max = curr.data
            curr = curr.next
      return max
   def print_it(self):
      curr = self.head
      if (self.head == None):
         print("列表为空")
         return
      print("双向链表中的节点：")
      while curr != None:
         print(curr.data)
         curr = curr.next
my_instance = double_list()
print("正在向双向链表添加元素")
my_instance.add_data(10)
my_instance.add_data(24)
my_instance.add_data(54)
my_instance.add_data(77)
my_instance.add_data(92)
my_instance.print_it()
print("最大值节点是：")
print(my_instance.max_node())
print("最小值节点是：")
print(my_instance.min_node())

正在向双向链表添加元素
双向链表中的节点：
10
24
54
77
92
最大值节点是：
92
最小值节点是：
10