问使用Ajax到Google Books API on production时，有时会出现500错误

EN

@app.route("/_search_books")
def search_books():
   title = request.args.get('title')
   if title:
        title = title.encode('utf-8')
        url = 'https://www.googleapis.com/books/v1/volumes?q=' + title

        h = urlopen(url)
        data = json.load(h)

        books = []
        for i in range(len(data['items'])):
            try:
                title = data['items'][i]['volumeInfo']['title']
            except:
                title = None
            try:
                author = data['items'][i]['volumeInfo']['authors'][0]
            except:
                author = None
            try:
                publisher = data['items'][i]['volumeInfo']['publisher']
            except:
                publisher = None
            try:
                year = data['items'][i]['volumeInfo']['publishedDate']
            except:
                year = None
            try:
                thumbnail = data['items'][i]['volumeInfo']['imageLinks']['thumbnail']
            except:
                thumbnail = None
            try:
                page = data['items'][i]['volumeInfo']['pageCount']
            except:
                page = None
            books.append({'title': title, 'author': author, 'publisher': publisher, 'year': year, 'thumbnail': thumbnail, 'page': page})

        return jsonify(result=books)