def by_url(backend=None, loader=None):
 url = None
 if (backend and (u'://' in backend)):
  url = backend
  (scheme, _, _) = url.partition(u'://')
  if (u'+' in scheme):
   (backend, url) = url.split(u'+', 1)
  else:
   backend = scheme
 return (by_name(backend, loader), url)

def by_url ( backend = None , loader = None ) : url = None if ( backend and ( u'://' in backend ) ) : url = backend ( scheme , _ , _ ) = url . partition ( u'://' ) if ( u'+' in scheme ) : ( backend , url ) = url . split ( u'+' , 1 ) else : backend = scheme return ( by_name ( backend , loader ) , url )
get backend class by url .