code: func (uuid UUID) ClockSequence() (int, bool) {
  	if len(uuid) != 16 {
  		return 0, false
  	}
  	return int(binary.BigEndian.Uint16(uuid[8:10])) & 0x3fff, true
  }
docs: // ClockSequence returns the clock sequence encoded in uuid.  It returns false
  // if uuid is not valid.  The clock sequence is only well defined for version 1
  // and 2 UUIDs.