code: def main(_):
      hp = trainer_model_based_params.create_loop_hparams()
      assert not FLAGS.job_dir_to_evaluate
      training_loop(hp, FLAGS.output_dir)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import datetime
  import math
  import os
  import pprint
  import random
  import time
  import six
  from tensor2tensor.bin import t2t_trainer
  from tensor2tensor.models.research import rl
  from tensor2tensor.rl import rl_utils
  from tensor2tensor.rl import trainer_model_based_params
  from tensor2tensor.rl.dopamine_connector import DQNLearner
  from tensor2tensor.rl.restarter import Restarter
  from tensor2tensor.utils import trainer_lib
  import tensorflow.compat.v1
label_desc: Use image node_id 13 for calling a global function with example usage: main(_) without return types