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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 _gatk_extract_reads_cl(data, region, prep_params, tmp_dir):
 """Use GATK to extract reads from full BAM file. """

    args = ["PrintReads",
            "-L", region_to_gatk(region),
            "-R", dd.get_ref_file(data),
            "-I", data["work_bam"]]
    # GATK3 back compatibility, need to specify analysis type
    if "gatk4" in dd.get_tools_off(data):
        args = ["--analysis_type"] + args
    runner = broad.runner_from_config(data["config"])
    return runner.cl_gatk(args, tmp_dir)