爬取猫眼TOP100电影

import json
import re
import requests
from requests import RequestException
from  multiprocessing import Pool #引入进程池

def get_page(url):#获取网页
    try:
        headers={'User-Agent':
                'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.75 Safari/537.36'}
        response=requests.get(url,headers=headers)
        if response.status_code==200:
            return response.text
        return None
    except RequestException:
        return None

def parse_one_page(html):#正则表达式提取
    pattern=re.compile('<dd>.*?board-index.*?">(\d+?)</i>.*?title="(.*?)".*?<img.*?img.*?src='
                       '"(.*?)".*?>.*?"star">(.*?)</p>.*?"releasetime">(.*?)</p>.*?integer">(.*?)'
                       '</i>.*?fraction">(\d+?)</i>.*?</dd>',re.S)
    items=re.findall(pattern,html)
    for item in items:
        yield {
            '排名:':item[0],
            '电影:':item[1],
            '图片:':item[2],
            '主演:':item[3].strip()[3:],
            '上映时间:':item[4].strip()[5:],
            '评分:':item[5]+item[6]
        }

def write_file(content):#写入文件
    with open('movie.txt','a',encoding='utf-8') as f:#以utf-8编码新建
        f.write(json.dumps(content,ensure_ascii=False)+'\n')#不转为unicode编码


def main(page):
    url='http://maoyan.com/board/4'
    html=get_page(url=url+'?offset='+str(page*10))
   # print(html)
    items=parse_one_page(html)
    for item in items:
        write_file(item)

if __name__ == '__main__':
    #单进程
    '''
    for i in range(10):
        main(i)
    '''
    #多进程
    pool=Pool()
    pool.map(main,[i for i in range(10)])