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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(items):
 """Perform detection of structural variations with delly. Performs post-call filtering with a custom filter tuned based on NA12878 Moleculo and PacBio data, using calls prepared by @ryanlayer and @cc2qe Filters using the high quality variant pairs (DV) compared with high quality reference pairs (DR). """

    work_dir = utils.safe_makedir(os.path.join(items[0]["dirs"]["work"], "structural",
                                               dd.get_sample_name(items[0]), "delly"))
    # Add core request for delly
    config = copy.deepcopy(items[0]["config"])
    delly_config = utils.get_in(config, ("resources", "delly"), {})
    delly_config["cores"] = 1
    config["resources"]["delly"] = delly_config
    parallel = {"type": "local", "cores": config["algorithm"].get("num_cores", 1),
                "progs": ["delly"]}
    work_bams = [dd.get_align_bam(d) for d in items]
    ref_file = dd.get_ref_file(items[0])
    exclude_file = _get_full_exclude_file(items, work_bams, work_dir)
    bytype_vcfs = run_multicore(_run_delly,
                                [(work_bams, chrom, ref_file, work_dir, items)
                                 for chrom in sshared.get_sv_chroms(items, exclude_file)],
                                config, parallel)
    out_file = "%s.vcf.gz" % sshared.outname_from_inputs(bytype_vcfs)
    combo_vcf = vcfutils.combine_variant_files(bytype_vcfs, out_file, ref_file, config)
    out = []
    upload_counts = collections.defaultdict(int)
    for data in items:
        if "sv" not in data:
            data["sv"] = []
        base, ext = utils.splitext_plus(combo_vcf)
        final_vcf = sshared.finalize_sv(combo_vcf, data, items)
        if final_vcf:
            delly_vcf = _delly_count_evidence_filter(final_vcf, data)
            data["sv"].append({"variantcaller": "delly", "vrn_file": delly_vcf,
                               "do_upload": upload_counts[final_vcf] == 0,  # only upload a single file per batch
                               "exclude": exclude_file})
            upload_counts[final_vcf] += 1
        out.append(data)
    return out