python提取页面内url列表的方法

from bs4 import BeautifulSoup
import time,re,urllib2
t=time.time()
websiteurls={}
def scanpage(url):
 websiteurl=url
 t=time.time()
 n=0
 html=urllib2.urlopen(websiteurl).read()
 soup=BeautifulSoup(html)
 pageurls=[]
 Upageurls={}
 pageurls=soup.find_all("a",href=True)
 for links in pageurls:
 if websiteurl in links.get("href") and links.get("href") not in Upageurls and links.get("href") not in websiteurls:
 Upageurls[links.get("href")]=0
 for links in Upageurls.keys():
 try:
 urllib2.urlopen(links).getcode()
 except:
 print "connect failed"
 else:
 t2=time.time()
 Upageurls[links]=urllib2.urlopen(links).getcode()
 print n,
 print links,
 print Upageurls[links]
 t1=time.time()
 print t1-t2
 n+=1
 print ("total is "+repr(n)+" links")
 print time.time()-t
scanpage("http://news.163.com/")