input: Write a function to implement a linked list in Python using classes. The function should include a Node class to represent the node in the linked list and a LinkedList class to represent the entire linked list. The LinkedList class should have methods to initialize the linked list, create and link nodes, and print the linked list. The function should return the linked list after it has been created and linked.
  
  class Node:
      """Node class to represent the node in a linked list"""
      def __init__(self, data):
          self.data = data
          self.next = None
  
  class LinkedList:
      """LinkedList class to represent the entire linked list"""
      def __init__(self):
          self.head = None
      
      def print_list(self):
          node = self.head
          while(node):
              print(node.data)
              node = node.next
  
  linked_list = LinkedList()
  
  # Creating the nodes
  node1 = Node(1)
  node2 = Node(2)
  node3 = Node(3)
  
  # Linking the nodes
  linked_list.head = node1
  node1.next = node2
  node2.next = node3
  
  # Printing the linked list
  linked_list.print_list()
  
  assert linked_list.head.data == 1
  assert linked_list.head.next.data == 2
  assert linked_list.head.next.next.data == 3
  assert linked_list.head.next.next.next == None
output: def create_linked_list():
      class Node:
          """Node class to represent the node in a linked list"""
          def __init__(self, data):
              self.data = data
              self.next = None
  
      class LinkedList:
          """LinkedList class to represent the entire linked list"""
          def __init__(self):
              self.head = None
          
          def print_list(self):
              node = self.head
              while(node):
                  print(node.data)
                  node = node.next
  
      linked_list = LinkedList()
  
      # Creating the nodes
      node1 = Node(1)
      node2 = Node(2)
      node3 = Node(3)
  
      # Linking the nodes
      linked_list.head = node1
      node1.next = node2
      node2.next = node3
  
      return linked_list