import jsonimport reimport requestsfrom requests import RequestExceptionfrom  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 Nonedef parse_one_page(html):#正则表达式提取    pattern=re.compile('
     
      .*?board-index.*?">(\d+?).*?title="(.*?)".*?
      
       .*?"star">(.*?)
       
.*?"releasetime">(.*?)
       
.*?integer">(.*?)'                       '.*?fraction">(\d+?).*?
      
     
',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)])