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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(call_file, ref_file, vrn_files, data):
 """Run filtering on the input call file, handling SNPs and indels separately. """

    algs = [data["config"]["algorithm"]] * len(data.get("vrn_files", [1]))
    if includes_missingalt(data):
        logger.info("Removing variants with missing alts from %s." % call_file)
        call_file = gatk_remove_missingalt(call_file, data)

    if "gatkcnn" in dd.get_tools_on(data):
        return _cnn_filter(call_file, vrn_files, data)
    elif config_utils.use_vqsr(algs, call_file):
        if vcfutils.is_gvcf_file(call_file):
            raise ValueError("Cannot force gVCF output with joint calling using tools_on: [gvcf] and use VQSR. "
                             "Try using cutoff-based soft filtering with tools_off: [vqsr]")
        snp_file, indel_file = vcfutils.split_snps_indels(call_file, ref_file, data["config"])
        snp_filter_file = _variant_filtration(snp_file, ref_file, vrn_files, data, "SNP",
                                              vfilter.gatk_snp_cutoff)
        indel_filter_file = _variant_filtration(indel_file, ref_file, vrn_files, data, "INDEL",
                                                vfilter.gatk_indel_cutoff)
        orig_files = [snp_filter_file, indel_filter_file]
        out_file = "%scombined.vcf.gz" % os.path.commonprefix(orig_files)
        combined_file = vcfutils.combine_variant_files(orig_files, out_file, ref_file, data["config"])
        return combined_file
    else:
        snp_filter = vfilter.gatk_snp_cutoff(call_file, data)
        indel_filter = vfilter.gatk_indel_cutoff(snp_filter, data)
        return indel_filter