code: def on_image_saved(callback):
      """register a function to be called after an image is saved to a file.
      The callback is called with one argument:
          - params: ImageSaveParams - parameters the image was saved with. Changing fields in this object does nothing.
      """
      add_callback(callback_map["callbacks_image_saved"], callback)
  
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 33 for calling a global function with example usage: on_image_saved(callback) without return types