code: function getText(locale, ...args) {
      const key = args[0];
      if (!key) return null;
  
      // try locale
      let resource = ebLocales[locale] || {};
      let text = resource[key];
      if (text === undefined && locale !== 'en-us') {
        // try en-us
        resource = ebLocales['en-us'] || {};
        text = resource[key];
      }
      // equal key
      if (text === undefined) {
        text = key;
      }
      // format
      args[0] = text;
      return localeutil.getText.apply(localeutil, args);
    }
docs: based on koa-locales
  
  https://github.com/koajs/locales/blob/master/index.js