我有一个为我编写的脚本，我无法执行它...我收到以下错误...

回溯（最近的呼叫最后）：

文件“crawler.py”，第56行，在loop.run_until_complete（future）文件“C：\ Users \ lisa \ AppData \ Local \ Programs \ Python \ Python37-32 \ lib \ asyncio \ base_events.py”，第568行，在run_until_complete中返回future.result（）文件“crawler.py”，第51行，在运行中等待响应文件“crawler.py”，第32行，在bound_fetch中等待获取（url，session）文件“crawler.py”，行22，使用session.get（url，headers = headers）作为响应获取异步：文件“C：\ Users \ lisa \ AppData \ Local \ Programs \ Python \ Python37-32 \ lib \ site-packages \ aiohttp \ client . py“，第843行，在aenter self._resp = await self._coro文件”C：\ Users \ lisa \ AppData \ Local \ Programs \ Python \ Python37-32 \ lib \ site-packages \ aiohttp \ client.py“，第387行，在_request中等待resp.start（conn）文件“C：\ Users \ lisa \ AppData \ Local \ Programs \ Python \ Python37-32 \ lib \ site-packages \ aiohttp \ client_reqrep.py”，第748行，启动消息，payload = await self._protocol.read（）文件“C：\ Users \ lisa \ AppData \ Local \ Programs \ Python \ Python37-32 \ lib \ site-packages \ aiohttp \ streams.py”，line 533，在读取等待self._waiter aiohttp.client_exceptions.ServerDisconnectedError：无

有什么明显的东西我不见了吗？我可以在没有线程的情况下运行相同的脚本，谢谢......

import random
import asyncio
from aiohttp import ClientSession
import requests
from itertools import product
from string import *
from multiprocessing import Pool
from itertools import islice
import sys


headers = {'User-Agent': 'Mozilla/5.0'}

letter = sys.argv[1]
number = int(sys.argv[2])

first_group = product(ascii_lowercase, repeat=2)
second_group = product(digits, repeat=3)
codeList = [''.join([''.join(k) for k in prod]) for prod in product([letter], first_group, second_group)]

async def fetch(url, session):
    async with session.get(url, headers=headers) as response:
        statusCode = response.status
        if(statusCode == 200):
            print("{} statusCode is {}".format(url, statusCode))
        return await response.read()


async def bound_fetch(sem, url, session):
    async with sem:
        await fetch(url, session)

def getUrl(codeIdex):
    return "https://www.blahblah.com/" + codeList[codeIdex] + ".png"

async def run(r):
    tasks = []
    sem = asyncio.Semaphore(1000)

    async with ClientSession() as session:
        for i in range(r):
            task = asyncio.ensure_future(bound_fetch(sem, getUrl(i), session))
            tasks.append(task)

        responses = asyncio.gather(*tasks)
        await responses

loop = asyncio.get_event_loop()

future = asyncio.ensure_future(run(number))
loop.run_until_complete(future)
python multithreading python-asyncio