Inserting a node at the beginning of a linked list

In the previous exercise, you learned how to implement a Node() and LinkedList() class.

In this exercise, you will prepare the code for the insert_at_beginning() method to add a new node at the beginning of a linked list.

Recall the Node() class:

class Node:
  def __init__(self, data):
    self.data = data
    self.next = None

Create the new node.
Check whether the linked list has a head node.
If the linked list has a head node, point the next node of the new node to the head.