class Node:

  def __init__(self, data):

    self.data = data

    self.next = None

​

def traverseAndPrint(head):

  currentNode = head

  while currentNode:

    print(currentNode.data, end=" -> ")

    currentNode = currentNode.next

  print("null")

​

def deleteSpecificNode(head, nodeToDelete):

  if head == nodeToDelete:

    return head.next

​

  currentNode = head

  while currentNode.next and currentNode.next != nodeToDelete:

    currentNode = currentNode.next

​

  if currentNode.next is None:

    return head

​

  currentNode.next = currentNode.next.next

​

  return head

​

node1 = Node(7)

node2 = Node(11)

node3 = Node(3)

node4 = Node(2)

node5 = Node(9)

​

node1.next = node2

node2.next = node3

node3.next = node4

node4.next = node5

​

print("Before deletion:")

traverseAndPrint(node1)

​

# Delete node4

node1 = deleteSpecificNode(node1, node4)

​

print("\nAfter deletion:")

traverseAndPrint(node1)

​