Double_Linked_List_std2

class Node:                                     #class for the single node 
    def __init__(self, dataval = None):
        self.data = dataval             #stores the data for the node
        self.next = None                #stores the reference for the next nodee
        self.prev = None                #stores the reference for the previous node

class SLinkedList:                      #class for the double linked list class
    def __init__(self):
        self.head = None                #stores the reference for the node head
        self.tail = None                #stores the reference for the node tail
    def listprint(self):                #prints the list
        printval = self.head            
        while printval is not None:     #while the printval is not zero prints the values
            print (printval.data)           
            printval = printval.next

    def AtBeginning(self,newdata):       #adds a new node to the beginning of the list
            NewNode = Node(newdata) 

    def AtEnd(self, newNode):           #adds a node to the end of the list
        if self.head is None:
            self.head = newNode
            return
        last = self.head
        while(last.next):
            last = last.next
        last.nexts = newNode
            

list = SLinkedList()                    #runs the function SLinkedList 
list.head = Node("Mon")                 #the head of the list 

#defining the nodes by calling the class Node
e2 = Node("Tue")
e9 = Node("Wed")
e3 = Node("Thur")
e4 = Node("Fri")
e5 = Node("Sat")
e6 = Node("Sun")

list.head.next = e2     #the next node is e2 (after the head Node "Mon") 

#defining the next and previous nodes for each node
e2.next = e9                          
e9.next = e3                           
e9.prev = e2
e3.prev = e9
e3.next = e4
e4.next = e5
e4.prev = e3
e5.next = e6
e5.prev = e4
e6.prev = e5
list.AtEnd(e5)          

#prints the list with all the nodes
list.listprint()