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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 _piped_input_cl(data, region, tmp_dir, out_base_file, prep_params):
 """Retrieve the commandline for streaming input into preparation step. """

    return data["work_bam"], _gatk_extract_reads_cl(data, region, prep_params, tmp_dir)