code: def parse_leap_seconds(fileobj):
      lines = iter(fileobj)
      for line in lines:
          if line.startswith(b'
              break
      else:
          raise ValueError('Leap_Second.dat is missing its expiration date')
      line = line.decode('ascii')
      with _lock:
          original_locale = locale.setlocale(locale.LC_ALL)
          locale.setlocale(locale.LC_ALL, 'C')
          try:
              dt = datetime.strptime(line, '
          finally:
              locale.setlocale(locale.LC_ALL, original_locale)
      grace_period = timedelta(days=30)
      expiration_date = dt.date() + grace_period
      mjd, day, month, year, offsets = np.loadtxt(lines).T
      leap_dates = np.ndarray(len(mjd) + 2)
      leap_dates[0] = '-inf'
      leap_dates[1:-1] = mjd + 2400000.5
      leap_dates[-1] = 'inf'
      leap_offsets = np.ndarray(len(mjd) + 2)
      leap_offsets[0] = leap_offsets[1] = offsets[0]
      leap_offsets[2:] = offsets
      return expiration_date, (leap_dates, leap_offsets)