code: def list_unets_callback():
      res = []
  
      for c in callback_map["callbacks_list_unets"]:
          try:
              c.callback(res)
          except Exception:
              report_exception(c, "list_unets")
  
      return res
  
imports: import inspect
  import os
  from collections import namedtuple
  from typing import Optional, Any
  from fastapi import FastAPI
  from gradio import Blocks
  from modules import errors, timer
label_desc: Use image node_id 22 for calling a global function with example usage: list_unets_callback() and returns: res