没有声明全局变量，为什么出错。。

Question

代码如下，一直报错 —— UnboundLocalError: local variable 'dian' referenced before assignment
查了一下好像是说全局变量应用的问题，但是我好像并没有声明全局变量呀。这是哪里出差了？求解答

import requests
import re
def gethtml(url):
    try:
        headers={"user-agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 "
                               "(KHTML, like Gecko) Chrome/105.0.0.0 Safari/537.36"}
        req=requests.get(url,headers=headers)
        req.raise_for_statues()
        req.encoding=req.apparent_encoding
    except:
        return "error"
    return req.text
def getinfo(html):
    obj = re.compile(r'
.*?
.*?(?P<name>.*?)'
                     r'.*?
(?P<year>.*?) .*?(?P<score>.*?)'
                     r'.*?(?P<number>.*?)人评价', re.S)
    i = obj.finditer(html)
    for it in i:
        dian=it.groupdict()
        dian['year'] = dian['year'].strip()
    return dian
def main():
    url ='https://movie.douban.com/top250'
    html=gethtml(url)
    getinfo(html)
if __name__ == '__main__':
    main()

Answer 1