用Python爬取网页时，直接运行for语句下的代码可正常运行，加入for语句进行循环则报错
遇到的现象和发生背景，请写出第一个错误信息
def getHTMLText(url_):
try:
r = requests.get(url_, timeout=30)
r.raise_for_status() # 如果状态不是200，引发HTTPError异常
r.encoding = r.apparent_encoding
return r.text
except:
return "产生异常"
def getSoup(url_):
html_ = getHTMLText(url_)
soup_ = BeautifulSoup(html_, 'lxml')
return soup_
if __name__ == "__main__":
year = '23'
month = '01'
day = '04'
page = '01'
for page in range(1, 9): # 注释掉本行则可正常运行
target = f"http://paper.people.com.cn/rmrb/html/20{year}-{month}/{day}/nbs.D110000renmrb_{page}.htm"
soup = getSoup(target)
title_list = soup.find('ul',class_='news-list')
title_list = title_list.find_all('a')
for title in title_list:
print(title.string)
运行结果及详细报错内容Traceback (most recent call last):
File "C:\Users\songz\PycharmProjects\pythonProject1\spiders\spiderNews.py", line 47, in <module>
title_list = title_list.find_all('a')
AttributeError: 'NoneType' object has no attribute 'find_all'
如何能通过for语句循环运行？
