code: def flatten_vertex_dict_adder(
      nodes: List,
      nodes_hits: Set[str],
      item: dict,
      id_col: str = "id",
      label_col: str = "label",
  ) -> Optional[dict]:
      """
      Return item when added as fresh
      """
      id = None
      if "T.id" in item:
          id = item["T.id"]
      elif "id" in item:
          id = item["id"]
      if id is None or (id not in nodes_hits):
          d = flatten_vertex_dict(item, id_col, label_col)
          nodes.append(d)
          if id is not None:
              nodes_hits.add(id)
          return d
      return None
  
imports: from typing import Any, Callable, Iterable, List, Optional, Set, Union, TYPE_CHECKING
  import os, pandas
  from .Plottable import Plottable
  from .util import setup_logger
label_desc: Use image node_id 8 for calling a global function with example usage: flatten_vertex_dict_adder(nodes, nodes_hits, item, id_col, label_col) and returns: None, d