code: def get_authentic_node_name(self, node_name: str) -> Optional[str]:
          
          node: Node = self._nodes.get_node_by_name(node_name)
          return node.name if node is not None else None
docs: Returns the exact, authentic node name for the given node name if a node corresponding to
          the given name exists in the graph (maybe not locally yet) or `None` otherwise.
  
          By default, this method checks whether a node with the given name exists locally in the
          graph and return `node_name` if it does or `None` otherwise.
  
          In `Graph` extensions that are used by applications where the user can enter potentially
          incorrect node names, this method should be overridden to improve usability.
  
          Arguments:
              node_name (str): The node name to return the authentic node name for.
  
          Returns:
              The authentic name of the node corresponding to the given node name or
              `None` if no such node exists.