def do_pending_lookups(sender, **kwargs):
 key = (sender._meta.app_label, sender.__name__)
 for (cls, field, operation) in pending_lookups.pop(key, []):
  operation(field, sender, cls)

def do_pending_lookups ( sender , ** kwargs ) : key = ( sender . _meta . app_label , sender . __name__ ) for ( cls , field , operation ) in pending_lookups . pop ( key , [ ] ) : operation ( field , sender , cls )
handle any pending relations to the sending model .