code: def check_region(read, pair, region):
      
      if region is False:
          return True
      for mapping in read, pair:
          if mapping is False:
              continue
          start, length = int(mapping[3]), len(mapping[9])
          r = [start, start + length - 1]
          if get_overlap(r, region) > 0:
              return True
      return False
docs: determine whether or not reads map to specific region of scaffold