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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 _get_mapper_params(self):
 """Converts self to model.MapperSpec.params."""

    reader_params = self.input_reader_cls.params_to_json(
        self.input_reader_params)
    # TODO(user): Do the same for writer params.
    return {"input_reader": reader_params,
            "output_writer": self.output_writer_params}