code: def remove_polyx_regions(in_file, items):
      
      ex_bed = tz.get_in(["genome_resources", "variation", "polyx"], items[0])
      if ex_bed and os.path.exists(ex_bed):
          return _remove_regions(in_file, [ex_bed], "nopolyx", items[0])
      else:
          return in_file
docs: Remove polyX stretches, contributing to long variant runtimes.