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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 hyperparameters(self):
 """Return hyperparameters used by your custom Chainer code during training."""

        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