human
Solve the following python programming problem given the following code:
def is_active_feature(feature, redirect_to = None, redirect = None) : 
    "
  Decorator for Flask views. If a feature is off, it can either return a 404 or redirect to a URL if you'd rather.
  " 
    def _is_active_feature(func) : 
        @ wraps (func) 
        def wrapped(* args, **kwargs) : 
            if (not is_active (feature)) : 
                url = redirect_to 
                if redirect : 
                    url = url_for (redirect) 
if url : 
                    log.debug ('Feature {feature} is off, redirecting to {url}'.format (feature = feature, url = url)) 
                    return _redirect (url, code = 302) 
else : 
                    log.debug ('Feature {feature} is off, aborting request'.format (feature = feature)) 
                    abort (404) 
return func (* args, ** kwargs) 
return wrapped 
return <MASK> 
    
    Given the code above, what is a proper replacement for <MASK>?
assistant
#Here is a proper replacement for <MASK>.
def _is_active_feature(