Linked List | Set 2 (Inserting a node)

def insert(self, data):
    temp = Node(data)
    temp.next = self.head
    self.head = temp
def append_to_linked_list(self,new_data):
    temp = self.head
    new_node = Node(new_data)
    while(temp):
        if temp.next == None:
            temp.next = new_node
            return
        else:
            temp = temp.next
def add_at_first(self,new_data):
    new_node = Node(new_data)
    new_node.next= self.head
    self.head = new_node
def inser_after(self,prev_node, new_data):
    new_node = Node(new_data)
    new_node.next = prev_node.next
    prev_node.next = new_node