Decodes from dataset or file.

def decode(self,
             dataset_split=None,
             decode_from_file=False,
             checkpoint_path=None):
    """Decodes from dataset or file."""
    if decode_from_file:
      decoding.decode_from_file(self._estimator,
                                self._decode_hparams.decode_from_file,
                                self._hparams,
                                self._decode_hparams,
                                self._decode_hparams.decode_to_file)
    else:
      decoding.decode_from_dataset(
          self._estimator,
          self._hparams.problem.name,
          self._hparams,
          self._decode_hparams,
          dataset_split=dataset_split,
          checkpoint_path=checkpoint_path)