re.findall()返回空列表

import re
import requests

if __name__=='__main__':
    url = 'https://www.qiushibaike.com/imgrank/'
    headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.85 Safari/537.36'}

    page_text = requests.get(url=url, headers=headers).text
    # <div class="thumb">
    # <a href="/article/124293385" target="_blank">
    # <img src="//pic.qiushibaike.com/system/pictures/12429/124293385/medium/XEYQOYMNVEQP8RA1.jpg" alt="糗事#124293385" class="illustration" width="100%" height="auto">
    # </div>
    ex = '<div class="thumb">.*?<img src="(.*?)" atl.*?</div>'
    img_src_list = re.findall(ex, page_text, re.S)
    print(img_src_list)

红框内应为alt，题主写错了。另外，正则表达式前面加r，可以避免很多麻烦，是一个好习惯。

啥问题