python使用BeautifulSoup分页网页中超链接的方法

from BeautifulSoup import BeautifulSoup
import urllib2
import re
url = urllib2.urlopen("https://www.jb51.net")
content = url.read()
soup = BeautifulSoup(content)
for a in soup.findAll('a',href=True):
  if re.findall('sharejs', a['href']):
    print "Found the URL:", a['href']