def insert(self, n, value):
if n > self.count:
raise IndexError('Index out of range')
node = self.get_node(n)
newNode = Node(value, node.prev, node)
node.prev.next = newNode
node.prev = newNode
self.count += 1
def prepend(self, value):
newNode = Node(value, self.head, self.head.next)
self.head.next.prev = newNode
self.head.next = newNode
self.count += 1
def append(self, value):
newNode = Node(value, self.head.prev, self.head)
self.head.prev.next = newNode
self.head.prev = newNode
self.count += 1
def clear(self):
self.head = Node()
self.head.prev = self.head
self.head.next = self.head
self.count = 0