code: def _annotate(args, setclus):
      
      logger.info("Creating bed file")
      bedfile = generate_position_bed(setclus)
      a = pybedtools.BedTool(bedfile, from_string=True)
      beds = []
      logger.info("Annotating clusters")
      if hasattr(args, 'list_files'):
          beds = args.list_files.split(",")
          for filebed in beds:
              logger.info("Using %s " % filebed)
              db = os.path.basename(filebed)
              b = pybedtools.BedTool(filebed)
              c = a.intersect(b, wo=True)
              setclus = anncluster(c, setclus, db, args.type_ann, args.feature_id)
      return setclus
docs: annotate transcriptional units with
      gtf/bed files provided by -b/g option