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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 calculate_sv_coverage(data):
 """Calculate coverage within bins for downstream CNV calling. Creates corrected cnr files with log2 ratios and depths. """

    calcfns = {"cnvkit": _calculate_sv_coverage_cnvkit, "gatk-cnv": _calculate_sv_coverage_gatk}
    from bcbio.structural import cnvkit
    data = utils.to_single_data(data)
    if not cnvkit.use_general_sv_bins(data):
        out_target_file, out_anti_file = (None, None)
    else:
        work_dir = utils.safe_makedir(os.path.join(dd.get_work_dir(data), "structural",
                                                   dd.get_sample_name(data), "bins"))
        out_target_file, out_anti_file = calcfns[cnvkit.bin_approach(data)](data, work_dir)
        if not os.path.exists(out_target_file):
            out_target_file, out_anti_file = (None, None)
    if "seq2c" in dd.get_svcaller(data):
        from bcbio.structural import seq2c
        seq2c_target = seq2c.precall(data)
    else:
        seq2c_target = None

    if not tz.get_in(["depth", "bins"], data):
        data = tz.update_in(data, ["depth", "bins"], lambda x: {})
    data["depth"]["bins"] = {"target": out_target_file, "antitarget": out_anti_file, "seq2c": seq2c_target}
    return [[data]]