python 协程 图片下载案例

import urllib.request
import gevent
from gevent import monkey

monkey.patch_all()


def downloader(img_name, img_url):
    req = urllib.request.urlopen(img_url)

    img_content = req.read()

    with open(img_name, "wb") as f:
        f.write(img_content)

def main():
    gevent.joinall([
            gevent.spawn(downloader, "3.jpg", "https://rpic.douyucdn.cn/appCovers/2017/09/22/1760931_20170922133718_big.jpg"),
            gevent.spawn(downloader, "4.jpg", "https://rpic.douyucdn.cn/appCovers/2017/09/17/2308890_20170917232900_big.jpg")
    ])


if __name__ == ‘__main__‘:
    main()