python爬虫爬取豆瓣电影top250报错

刚开始学爬虫，最近在看视频，代码和视频是一样的但是出现了报错，无法解决麻烦大家看一下是什么情况。（并不是完整的爬虫，只是一个中间过程出现了报错 - -）

问题相关代码，请勿粘贴截图

# -*- coding = urf-8 -*-
import urllib.request  # 制定URL，获得网页数据


def main():
    baseurl = 'https://movie.douban.com/top250?start=0'
    # 1.爬取网页
    datalist = getData(baseurl)
    savepath = ".\\豆瓣top250.xls"
    # saveData(savepath)
    askURL("https://movie.douban.com/top250?start=0")


# 爬取网页
def getData(baseurl):
    datalist = []
    # 2.解析数据
    return datalist


# 指定一个URL的网页内容
def askURL(url):
    # 模拟头部信息，像豆瓣服务器发送消息
    head = {
        "User-Agent"": Mozilla/5.0 (Linux; Android 6.0; Nexus 5 Build/MRA58N) "
        "AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.45 Mobile Safari/537.36"
    }
    # 用户代理告诉豆瓣服务器，我们是什么类型的机器、浏览器（本质上是高速浏览器我能接受什么类型的数据）
    request = urllib.request.Request(url, headers=head)
    html = ""
    try:
        response = urllib.request.urlopen(request)
        html = response.read().decode("utf-8")
    except Exception as e:
        print(e)
    return html


# 3.保存数据
def saveData(savepath):
    print('saving ...')


if __name__ == "__main__":
    main()

运行结果及报错内容

Traceback (most recent call last):
  File "D:\pythonworld\codecode\pythonscrpit\weishabudui.py", line 49, in <module>
    main()
  File "D:\pythonworld\codecode\pythonscrpit\weishabudui.py", line 15, in main
    askURL("https://movie.douban.com/top250?start=0")
  File "D:\pythonworld\codecode\pythonscrpit\weishabudui.py", line 30, in askURL
    request = urllib.request.Request(url, headers=head)
  File "C:\Users\30295\AppData\Local\Programs\Python\Python39\lib\urllib\request.py", line 326, in __init__
    for key, value in headers.items():
AttributeError: 'set' object has no attribute 'items'

Process finished with exit code 1

补充一下，文中30行报错应该是29行，粘贴过来时候把前面不需要的库删掉了。不好意思哈