code: def hyperparameters(self):
          
          hyperparameters = super(Chainer, self).hyperparameters()
  
          additional_hyperparameters = {Chainer._use_mpi: self.use_mpi,
                                        Chainer._num_processes: self.num_processes,
                                        Chainer._process_slots_per_host: self.process_slots_per_host,
                                        Chainer._additional_mpi_options: self.additional_mpi_options}
  
          # remove unset keys.
          additional_hyperparameters = {k: v for k, v in additional_hyperparameters.items() if v}
          hyperparameters.update(Framework._json_encode_hyperparameters(additional_hyperparameters))
          return hyperparameters
docs: Return hyperparameters used by your custom Chainer code during training.