docs: def generate_lines(input_file,
                     start=0,
                     stop=float('inf')):
      """Generate (yield) lines in a gzipped file (*.txt.gz) one line at a time"""
      with gzip.GzipFile(input_file, 'rU') as f:
          for i, line in enumerate(f):
              if i < start:
                  continue
              if i >= stop:
                  break
              yield line.rstrip()