def addToTail(self, value):
newNode = Node(value)
if not self.tail:
self.head = newNode
else:
self.tail.next = newNode
newNode.prev = self.tail
self.items.append(newNode)
self.tail = newNode
def insertAtIndex(self, index, value):
if index > len(self.items) - 1:
return False
if index == 0:
return self.addToHead(value)
if index == len(self.items) - 1:
return self.addToTail(value)
new_node = Node(value)
before_node = self.items[index - 1]
after_node = self.items[index]
before_node.next = new_node
new_node.prev = before_node
after_node.prev = new_node
new_node.next = after_node
self.items.insert(index, new_node)