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

   def add_data(self,my_data):  
      new_node = Node(my_data)  
      if self.head.data is None:  
         self.head = new_node  
         self.tail = new_node  
         new_node.next = self.head  
      else:  
         self.tail.next = new_node  
         self.tail = new_node  
         self.tail.next = self.head  

   def find_min_node(self):  
      curr = self.head;  
      min_val = self.head.data;  
      if(self.head == None):  
         print("The list is empty");  
      else:  
         while(True):  
            if(min_val > curr.data):  
               min_val = curr.data;  
            curr= curr.next;  
            if(curr == self.head):  
               break;  
      print("Minimum value node in the list: "+ str(min_val));  
   
   def find_max_node(self):  
      curr = self.head;  
      max_val = self.head.data;  
      if(self.head == None):  
         print("List is empty");  
      else:  
         while(True):  
            if(max_val < curr.data):  
               max_val = curr.data;  
            curr= curr.next;  
            if(curr == self.head):  
               break;  
      print("The maximum valued node is : "+ str(max_val));
   
class circular_linked_list:  
   my_cl = list_creation()
   print("Values have been added to the list")
   my_cl.add_data(11)  
   my_cl.add_data(52)  
   my_cl.add_data(36)  
   my_cl.add_data(74)  
   my_cl.find_max_node()
   my_cl.find_min_node()

Values have been added to the list
The maximum valued node is : 74
Minimum value node in the list: 11