Show FileBox

def show_input(self, template_helper, language, seed):
        """ Show FileBox """
        header = ParsableText(self.gettext(language, self._header), "rst",
                              translation=self._translations.get(language, gettext.NullTranslations()))
        return str(DisplayableFileProblem.get_renderer(template_helper).tasks.file(self.get_id(), header, self._max_size, self._allowed_exts))