Extract link from website

import sys
import urllib2
import re
def find_link(url):
    sys.stdout.write("\nWait a Minute its retrieving.\n")
    try:
        if url[0:4]!="http":
            url="http://" + url
        f=(urllib2.urlopen(url)).read()
        k=re.findall('(src|href)="(\S+)"',f)
        k=set(k)
        print "\nThe Links are:------------\n"
        for x in k:
            if len(x[1])>2:
                print x[1]
    except:
        print "NOT found plz check url"
def usage():
    print """
\n______________________________________________\n
Usage : python file.py url
\n______________________________________________\n
"""
if __name__ == "__main__":
    print """
\n-------------------------------------------------------------
\n   ___ ________  ___ ___________________  ______\n  / _ /_  /_  / / _ /_  __/ __/ __/  _/ |/ / __/\n / __ |/ /_/ /_/ __ |/ / _\ \_\ \_/ //    /\ \  \n/_/ |_/___/___/_/ |_/_/ /___/___/___/_/|_/___/  \n                                                \n
--------------------------------------------------------------\n"""
    if len(sys.argv)==1:
        usage()
    else:
        find_link(sys.argv[1])