code: def _parse_octet(self, octet_str):
          
          # Whitelist the characters, since int() allows a lot of bizarre stuff.
          if not self._DECIMAL_DIGITS.issuperset(octet_str):
              raise ValueError
          octet_int = int(octet_str, 10)
          # Disallow leading zeroes, because no clear standard exists on
          # whether these should be interpreted as decimal or octal.
          if octet_int > 255 or (octet_str[0] == '0' and len(octet_str) > 1):
              raise ValueError
          return octet_int
docs: Convert a decimal octet into an integer.
  
          Args:
              octet_str: A string, the number to parse.
  
          Returns:
              The octet as an integer.
  
          Raises:
              ValueError: if the octet isn't strictly a decimal from [0..255].