def pick_protocols(self, step_num, step_type):

        # wrapping functionality like this makes testing much simpler
        p_read, p_write = self._pick_protocol_instances(step_num, step_type)

        return p_read.read, p_write.write

    ### Command-line arguments ###
Pick the protocol classes to use for reading and writing for the
dataset/ETHPy150Open Yelp/mrjob/mrjob/job.py/MRJob.pick_protocols