code: function suggest (opts) {
    return new Promise(function (resolve) {
      if (!opts && !opts.term) {
        throw Error('term missing');
      }
  
      return resolve(BASE_URL + encodeURIComponent(opts.term));
    })
      .then(url => common.request(url, {}, opts.requestOptions))
      .then(parseXML)
      .then(extractSuggestions);
  }
docs: TODO see language Accept-Language: en-us, en;q=0.50