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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def main(_):
 """Load a trained algorithm and render videos."""

  utility.set_up_logging()
  if not FLAGS.logdir or not FLAGS.outdir:
    raise KeyError('You must specify logging and outdirs directories.')
  FLAGS.logdir = os.path.expanduser(FLAGS.logdir)
  FLAGS.outdir = os.path.expanduser(FLAGS.outdir)
  visualize(
      FLAGS.logdir, FLAGS.outdir, FLAGS.num_agents, FLAGS.num_episodes,
      FLAGS.checkpoint, FLAGS.env_processes)