os.system("cls")
print(Fore.LIGHTGREEN_EX, "\n\t1.审批新闻")
print(Fore.LIGHTGREEN_EX, "\n\t2.删除新闻")
print(Fore.BLUE, "\n\t---------------")
print(Fore.LIGHTRED_EX, "\n\tback.返回上一层")
print(Style.RESET_ALL)
opt = input("\n\t请输入操作编号：")
# 审批新闻
if opt == "1":
    page = 1
    while True:
        os.system("cls")
        count_page = __news_service.search_unreview_count_page()
        result = __news_service.search_unreview_list(page)
        for index in range(len(result)):
            one = result[index]
            print(Fore.LIGHTBLUE_EX, "\n\t{}\t{}\t{}\t{}".format((index+1), one[1], one[2], one[3]))
        print("\n")
        print(Fore.LIGHTBLUE_EX, "\n\t{}/{}".format(page, count_page))
        print(Fore.BLUE, "\n\t-------------------------------")
        print(Fore.LIGHTRED_EX, "\n\tback.返回上一层")
        print(Fore.LIGHTRED_EX, "\n\tprev.上一页")
        print(Fore.LIGHTRED_EX, "\n\tnext.下一页")
        print(Style.RESET_ALL)
        opt = input("\n\t请输入操作编号：")
        if int(opt) >= 1 and int(opt) <= 10:
            news_id = result[int(opt)-1][0]
            __news_service.update_unreview_news(news_id)
        elif opt == "back":
            break
        elif opt == "prev" and page > 1:
            page -= 1
        elif opt == "next" and page < count_page:
            page += 1

程序运行后可循环审核两条，审核第三条时报错

Failed getting connection; pool exhausted

Traceback (most recent call last):

  File "E:\PythonLearn\Work\Vega\vega01\app.py", line 143, in <module>

    for index in range(len(result_insert)):

TypeError: object of type 'NoneType' has no len()

提示对象没有len()属性