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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 run_region(data, region, vrn_files, out_file):
 """Perform variant calling on gVCF inputs in a specific genomic region. """

    broad_runner = broad.runner_from_config(data["config"])
    if broad_runner.gatk_type() == "gatk4":
        genomics_db = _run_genomicsdb_import(vrn_files, region, out_file, data)
        return _run_genotype_gvcfs_genomicsdb(genomics_db, region, out_file, data)
    else:
        vrn_files = _batch_gvcfs(data, region, vrn_files, dd.get_ref_file(data), out_file)
        return _run_genotype_gvcfs_gatk3(data, region, vrn_files, dd.get_ref_file(data), out_file)