human
Solve the following python programming problem given the following code:
def __call__(self, request, * args, **kwargs) : 
    '
        Calls the underlying service method.

        @return: A C{Deferred} that will contain the AMF L{Response}.
        @rtype: C{twisted.internet.defer.Deferred}
        ' 
    try : 
        service_request = self.gateway.getServiceRequest (request, request.target) 
except gateway.UnknownServiceError : 
        return defer.succeed (self.buildErrorResponse (request)) 
response = remoting.Response (None) 
    deferred_response = defer.Deferred () 
    def eb(failure) : 
        errMesg = ('%s: %s' % (failure.type, failure.getErrorMessage ())) 
        if self.gateway.logger : 
            self.gateway.logger.error (errMesg) 
            self.gateway.logger.info (failure.getTraceback ()) 
deferred_response.callback (self.buildErrorResponse (request, (failure.type, failure.value, failure.tb))) 
def response_cb(result) : 
        if self.gateway.logger : 
            self.gateway.logger.debug (('AMF Response: %s' % (result,))) 
response.body = result 
        deferred_response.callback (response) 
def preprocess_cb(result) : 
        d = defer.maybeDeferred (self._getBody, request, response, service_request, ** kwargs) 
        d.addCallback (response_cb).addErrback (eb) 
def auth_cb(result) : 
        if (result is not True) : 
            response.status = remoting.STATUS_ERROR 
            response.body = remoting.ErrorFault (code = 'AuthenticationError', description = 'Authentication failed') 
            deferred_response.callback (response) 
            return 
d = defer.maybeDeferred (self.gateway.preprocessRequest, service_request, * args, ** kwargs) 
        d.addCallback (preprocess_cb).addErrback (eb) 
d = defer.maybeDeferred (self.authenticateRequest, request, response, ** kwargs) 
    d.addCallback (auth_cb).addErrback (eb) 
    return deferred_response 

    
    

    Fix the buggy line: d = defer.maybeDeferred (self.authenticateRequest, request, response, ** kwargs)
assistant
#Here is Python program to fix the buggy line: d = defer.

d = defer.maybeDeferred (self.authenticateRequest, request, service_request, ** kwargs)