python3.8 安装 jupyter,运行时提示NotImplementedError

issue地址

https://github.com/jupyter/notebook/issues/4613
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具体方案

找到报错信息提示的XXX\tornado\platform\asyncio.py 文件
添加如下代码：

import asyncio
import sys
if sys.platform == 'win32' and sys.version_info > (3, 8, 0, 'alpha', 3) :
    asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())