code: def create_agent_from_model_file(model_file, opt_overrides=None):
      """
      Load agent from model file if it exists.
  
      :param opt_overrides:
          An optional dict of option overrides can also be provided.
      :return:
          The agent
      """
      opt = {}
      add_datapath_and_model_args(opt)
      opt["model_file"] = modelzoo_path(opt.get("datapath"), model_file)
      if opt_overrides is None:
          opt_overrides = {}
      opt["override"] = opt_overrides
      return create_agent_from_opt_file(opt)
  
imports: import copy
  from typing import List, Union
  from parlai.core.build_data import modelzoo_path
  from parlai.core.loader import load_agent_module
  from parlai.core.loader import register_agent
  from parlai.core.message import Message
  from parlai.core.opt import Opt
  from parlai.utils.misc import warn_once
  import parlai.utils.logging
  from parlai.utils.io import PathManager
label_desc: Use image node_id 2 for calling a global function with example usage: create_agent_from_model_file(model_file, opt_overrides) and returns: create_agent_from_opt_file