def generator_eos(nbr_symbols, max_length, nbr_cases):
      """Shift by NUM_RESERVED_IDS and append EOS token."""
      for case in self.generator(nbr_symbols, max_length, nbr_cases):
        new_case = {}
        for feature in case:
          new_case[feature] = [
              i + text_encoder.NUM_RESERVED_TOKENS for i in case[feature]
          ] + [text_encoder.EOS_ID]
        yield new_case
Shift by NUM_RESERVED_IDS and append EOS token.
tensor2tensor/data_generators/algorithmic.py