获取城市的PM2.5浓度和排名（含单线程和多线程），pm2.5单线程,#!/usr/bin/e

获取城市的PM2.5浓度和排名（含单线程和多线程），pm2.5单线程,#!/usr/bin/e

#!/usr/bin/env python# -*- coding: utf-8 -*-# by ustcwqimport urllib2import threadingfrom time import ctimefrom bs4 import BeautifulSoupdef getPM25(cityname):    site = 'http://www.pm25.com/' + cityname + '.html'    html = urllib2.urlopen(site)    soup = BeautifulSoup(html)    city = soup.find(class_ = 'bi_loaction_city')   # 城市名称    aqi = soup.find("a",{"class","bi_aqiarea_num"})  # AQI指数    quality = soup.select(".bi_aqiarea_right span")  # 空气质量等级    result = soup.find("div",class_ ='bi_aqiarea_bottom')   # 空气质量描述    print city.text + u'AQI指数：' + aqi.text + u'\n空气质量：' + quality[0].text + result.text    print '*'*20 + ctime() + '*'*20def one_thread():   # 单线程    print 'One_thread Start: ' + ctime() + '\n'    getPM25('hefei')    getPM25('shanghai')def two_thread():   # 多线程    print 'Two_thread Start: ' + ctime() + '\n'    threads = []    t1 = threading.Thread(target=getPM25,args=('hefei',))    threads.append(t1)    t2 = threading.Thread(target=getPM25,args=('shanghai',))    threads.append(t2)    for t in threads:        # t.setDaemon(True)        t.start()if __name__ == '__main__':    one_thread()    print '\n' * 2    two_thread()