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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 _add_variantcalls_to_output(out, data, items, is_somatic=False):
 """Call ploidy and convert into VCF and BED representations. """

    call_file = "%s-call%s" % os.path.splitext(out["cns"])
    if not utils.file_exists(call_file):
        with file_transaction(data, call_file) as tx_call_file:
            filters = ["--filter", "cn"]
            cmd = [os.path.join(os.path.dirname(sys.executable), "cnvkit.py"), "call"] + \
                  filters + \
                   ["--ploidy", str(ploidy.get_ploidy([data])),
                    "-o", tx_call_file, out["cns"]]
            small_vrn_files = _compatible_small_variants(data, items)
            if len(small_vrn_files) > 0 and _cna_has_values(out["cns"]):
                cmd += ["--vcf", small_vrn_files[0].name, "--sample-id", small_vrn_files[0].sample]
                if small_vrn_files[0].normal:
                    cmd += ["--normal-id", small_vrn_files[0].normal]
                if not is_somatic:
                    cmd += ["-m", "clonal"]
            gender = _get_batch_gender(items)
            if gender:
                cmd += ["--sample-sex", gender]
            do.run(cmd, "CNVkit call ploidy")
    calls = {}
    for outformat in ["bed", "vcf"]:
        out_file = "%s.%s" % (os.path.splitext(call_file)[0], outformat)
        calls[outformat] = out_file
        if not os.path.exists(out_file):
            with file_transaction(data, out_file) as tx_out_file:
                cmd = [os.path.join(os.path.dirname(sys.executable), "cnvkit.py"), "export",
                       outformat, "--sample-id", dd.get_sample_name(data),
                       "--ploidy", str(ploidy.get_ploidy([data])),
                       "-o", tx_out_file, call_file]
                do.run(cmd, "CNVkit export %s" % outformat)
    out["call_file"] = call_file
    out["vrn_bed"] = annotate.add_genes(calls["bed"], data)
    effects_vcf, _ = effects.add_to_vcf(calls["vcf"], data, "snpeff")
    out["vrn_file"] = effects_vcf or calls["vcf"]
    out["vrn_file"] = shared.annotate_with_depth(out["vrn_file"], items)
    return out