def message_from(results)
        if results[:response_code] == DECLINED
          return CVVResult.messages[results[:card_code]] if CARD_CODE_ERRORS.include?(results[:card_code])
          return AVSResult.messages[results[:avs_result_code]] if AVS_REASON_CODES.include?(results[:response_reason_code]) && AVS_ERRORS.include?(results[:avs_result_code])
        end