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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 decode(estimator, hparams, decode_hp):
 """Decode from estimator. Interactive, from file, or from dataset."""

  if FLAGS.decode_interactive:
    if estimator.config.use_tpu:
      raise ValueError("TPU can only decode from dataset.")
    decoding.decode_interactively(estimator, hparams, decode_hp,
                                  checkpoint_path=FLAGS.checkpoint_path)
  elif FLAGS.decode_from_file:
    decoding.decode_from_file(estimator, FLAGS.decode_from_file, hparams,
                              decode_hp, FLAGS.decode_to_file,
                              checkpoint_path=FLAGS.checkpoint_path)
    if FLAGS.checkpoint_path and FLAGS.keep_timestamp:
      ckpt_time = os.path.getmtime(FLAGS.checkpoint_path + ".index")
      os.utime(FLAGS.decode_to_file, (ckpt_time, ckpt_time))
  else:
    decoding.decode_from_dataset(
        estimator,
        FLAGS.problem,
        hparams,
        decode_hp,
        decode_to_file=FLAGS.decode_to_file,
        dataset_split="test" if FLAGS.eval_use_test_set else None,
        checkpoint_path=FLAGS.checkpoint_path)