def apply_method(self, r, **attr):
        """
            Entry point for REST API

            @param r: the S3Request
            @param attr: controller arguments
        """

        if r.representation != "xls":
            r.error(415, current.ERROR.BAD_FORMAT)

        template_id = r.id
        template = r.record
        if not template:
            r.error(405, current.ERROR.BAD_METHOD)

        T = current.T
        try:
            import xlwt
        except ImportError:
            r.error(501, T("xlwt not installed, so cannot export as a Spreadsheet"))

        s3db = current.s3db
        db = current.db

        # Get the translate record
        table = s3db.survey_translate
        record = db(table.id == self.record_id).select(table.code,
                                                       table.language,
                                                       limitby=(0, 1)).first()
        if record is None:
            r.error(404, current.ERROR.BAD_RECORD)

        code = record.code
        lang_filename = "applications/%s/languages/%s.py" % (r.application,
                                                             code)
        try:
            from gluon.languages import read_dict
            strings = read_dict(lang_filename)
        except __HOLE__:
            strings = {}

        output = StringIO()

        book = xlwt.Workbook(encoding="utf-8")
        sheet = book.add_sheet(record.language)
        question_list = s3db.survey_getAllQuestionsForTemplate(template_id)
        original = {}
        original[template.name] = True
        if template.description != "":
            original[template.description] = True

        for qstn in question_list:
            original[qstn["name"]] = True
            widget_obj = survey_question_type[qstn["type"]](question_id = qstn["qstn_id"])
            if isinstance(widget_obj, S3QuestionTypeOptionWidget):
                option_list = widget_obj.getList()
                for option in option_list:
                    original[option] = True
        sections = s3db.survey_getAllSectionsForTemplate(template_id)

        for section in sections:
            original[section["name"]] = True
            section_id = section["section_id"]
            layout_rules = s3db.survey_getQstnLayoutRules(template_id, section_id)
            layout_str = str(layout_rules)
            posn = layout_str.find("heading")
            while posn != -1:
                start = posn + 11
                end = layout_str.find("}", start)
                original[layout_str[start:end]] = True
                posn = layout_str.find("heading", end)

        row = 0
        sheet.write(row, 0, u"Original")
        sheet.write(row, 1, u"Translation")
        original_list = original.keys()
        original_list.sort()

        for text in original_list:
            row += 1
            original = s3_unicode(text)
            sheet.write(row, 0, original)
            if (original in strings):
                sheet.write(row, 1, s3_unicode(strings[original]))

        book.save(output)

        from gluon.contenttype import contenttype
        filename = "%s.xls" % code

        headers = current.response.headers
        headers["Content-Type"] = contenttype(".xls")
        headers["Content-disposition"] = "attachment; filename=\"%s\"" % filename

        output.seek(0)
        return output.read()

# =============================================================================
dataset/ETHPy150Open sahana/eden/modules/s3db/survey.py/survey_TranslateDownload.apply_method