提取URL地址中的域名與端口

import urllib    
proto, rest = urllib.splittype("http://blog.csdn.net/djd1234567")   
print proto,rest 

host, rest = urllib.splithost(rest)
print host,rest 

host, port = urllib.splitport(host)  
print host,port
 
if port is None:    
    port = 80    
print port