在python 3.8中使用aiohttp和asyncio关闭异常事件循环

我正在使用asyncio和aiohttp发出并发请求。我最近将Python升级到3.8.0版RuntimeError: Event loop is closed，程序运行后得到提示。

import asyncio
import aiohttp

async def do_call(name,session):
    async with session.get('https://www.google.be') as response:
        await response.text()
        return 'ok - {}'.format(Name)

async def main():
    async with aiohttp.ClientSession() as session:
        tasks = [do_call(str(i),session) for i in range(0,4)]
        results = await asyncio.gather(*tasks)
        print(results)

asyncio.run(main())

我确实从asyncio.gather（）获得了有效的结果，但是退出时会引发异常。我想更改代码，以免发生异常。

追溯如下：

Exception ignored in: <function _ProactorBasePipeTransport.__del__ at 0x000001E9A92079D0>
TraceBACk (most recent call last):
  File "C:\Users\Jonas\ApPDAta\Local\Programs\Python\Python38\lib\asyncio\proactor_events.py",line 116,in __del__
    self.close()
  File "C:\Users\Jonas\ApPDAta\Local\Programs\Python\Python38\lib\asyncio\proactor_events.py",line 108,in close
    self._loop.call_soon(self._call_connection_lost,NonE)
  File "C:\Users\Jonas\ApPDAta\Local\Programs\Python\Python38\lib\asyncio\base_events.py",line 711,in call_soon
    self._check_closed()
  File "C:\Users\Jonas\ApPDAta\Local\Programs\Python\Python38\lib\asyncio\base_events.py",line 504,in _check_closed
    raise RuntimeError('Event loop is closed')
RuntimeError: Event loop is closed`