def get_challenge_for_url(url):
 if (not url):
  raise ValueError('URL cannot be None')
 url = parse.urlparse(url)
 return _cache.get(url.netloc)

def get_challenge_for_url ( url ) : if ( not url ) : raise ValueError ( 'URL cannot be None' ) url = parse . urlparse ( url ) return _cache . get ( url . netloc )
gets the challenge for the cached url .