python爬取網頁數據

import re
from urllib.request import urlopen
'''
爬取網頁數據信息
'''
def getPage(url):
    response = urlopen(url)
    return response.read().decode('utf-8')

def parsePage(s):
    ret = re.findall(
        '<div class="item">.*?<div class="pic">.*?<em .*?>(?P<id>\d+).*?<span class="title">(?P<title>.*?)</span>'
       '.*?<span class="rating_num" .*?>(?P<rating_num>.*?)</span>.*?<span>(?P<comment_num>.*?)評價</span>',s,re.S)
    return ret

def main(num):
    url = 'https://movie.douban.com/top250?start=%s&filter=' % num
    response_html = getPage(url)
    ret = parsePage(response_html)
    print(ret)

count = 0
for i in range(10):   # 10頁
    main(count)
    count += 25

# url從網頁上把代碼搞下來
# bytes decode ——> utf-8 網頁內容就是我的待匹配字符串
# ret = re.findall(正則，帶匹配的字符串)  #ret是所有匹配到的內容組成的列表