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/")