code: def node_insert_after(self, node, new_node):
          
  
          assert(not self.node_is_on_list(new_node))
          assert(node is not new_node)
  
          next = self.node_next(node)
          assert(next is not None)
          self.node_set_next(node, new_node)
          self.node_set_prev(new_node, node)
  
          self.node_set_next(new_node, next)
          self.node_set_prev(next, new_node)
docs: Insert the new node after node.