private function generateExecuteFragment() {
        $body = '';

        if ($this->operationDefinition->getNeedsSigning()) {
            $body .= '$request = $this->api->signRequest($request);'.PHP_EOL;
        }

        $body .= '$response = $this->api->execute($request, $this);'.PHP_EOL;
        $body .= '$this->response = $response;'.PHP_EOL;

        return $body; 
    }