Insert a node at the head of a linked list:

"""
 Insert Node at the begining of a linked list
 head input could be None as well for empty list
 Node is defined as

 class Node(object):

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

 return back the head of the linked list in the below method. 
"""

def Insert(head, data):
    if head == None:
        return (Node(data,None))
    curr_node = head
    x = Node(data,curr_node)
    return x