code: def _calculate_sv_bins_cnvkit(data, cnv_group, size_calc_fn):
      
      from bcbio.structural import cnvkit
      if dd.get_background_cnv_reference(data, "cnvkit"):
          target_bed, anti_bed = cnvkit.targets_from_background(dd.get_background_cnv_reference(data, "cnvkit"),
                                                                cnv_group.work_dir, data)
      else:
          target_bed, anti_bed = cnvkit.targets_w_bins(cnv_group.region_file, cnv_group.access_file,
                                                       size_calc_fn, cnv_group.work_dir, data)
      return target_bed, anti_bed, None
docs: Calculate structural variant bins using target/anti-target approach from CNVkit.