class Node:

def __init__(self, data):

self.data = data

self.next = None

self.prev = None

class DoublyLinkedList:

def __init__(self):

self.head = None

def append(self, data):

if self.head is None:

new_node = Node(data)

self.head = new_node

else:

new_node = Node(data)

cur = self.head

while cur.next:

cur = cur.next

cur.next = new_node

new_node.prev = cur

def prepend(self, data):

if self.head is None:

new_node = Node(data)

self.head = new_node

else:

new_node = Node(data)

self.head.prev = new_node

new_node.next = self.head

self.head = new_node

def print_list(self):

cur = self.head

while cur:

print(cur.data)

cur = cur.next

dllist = DoublyLinkedList()

dllist.prepend(0)

dllist.append(1)

dllist.append(2)

dllist.append(3)

dllist.append(4)

dllist.prepend(5)

dllist.print_list()