[人工智能]Python 爬取豆瓣top250

#第一步，拿到源代码 requests
#第二步拿到想要的数据 re
import re
import requests
import csv

for page in range(0,226,25):
    url = "https://movie.douban.com/top250?start=%s&filter="%page
    print(url)
    header = {"User-Agent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36"}
    resp = requests.get(url,headers=header)
    page_content = resp.text #网页源代码保存在这
#第二步
    obj = re.compile('<div class="item">.*?<span class="title">(?P<name>.*?)</span>.*?<p class="">.*?<br>(?P<year>.*?)&nbsp.*?<div class="star">.*?<span class="rating_num" property="v:average">(?P<score>.*?)</span>.*?<span property="v:best" content="10.0"></span>.*?<span>(?P<number>.*?)</span>',re.S)
    result = obj.finditer(page_content)
# with open("data.csv","w",encoding="utf-8") as f: 没成功
    f = open("data.csv",mode="a+",encoding='utf-8') #创建一个csv文件 mode="w",mode = "a"持续写入不覆盖
    csvwrite = csv.writer(f)#具有写入的功能
    for i in result:
    # print(i.group("name"))
    # print(i.group("year").strip())#.strip()作用是去掉多余的空格
    # print(i.group("score").strip())#.strip()作用是去掉多余的空格
    # print(i.group("number").strip())#.strip()作用是去掉多余的空格
        dic = i.groupdict()#将(?P<名>.*?)的值存入字典
        dic['year'] = dic['year'].strip()#因为year前边有空格，所以给它去掉空格
        csvwrite.writerow(dic.values())#将字典里值写入csv文件
    f.close()
    resp.close()              

犯过的错误：

1.循环要对齐，格式要对齐
2.mode =‘a’ 如果是w就会出现只有一页数据的现象
r 只读模式
w 写模式
a 追加写模式