private static function callFunction($model, $key, $args, $numArgs = false, $valorRelleno = false) {
        if ($numArgs === false) {
            $numArgs = \Sirgrimorum\CrudGenerator\CrudGenerator::isFunction($model, $key);
        }
        if ($numArgs !== false) {
            if ($numArgs > count($args)) {
                for ($i = 0; $i <= ($numArgs - count($args)); $i++) {
                    $args[] = $valorRelleno;
                }
            } elseif ($numArgs < count($args)) {
                for ($i = 0; $i <= (count($args) - $numArgs); $i++) {
                    array_pop($args);
                }
            }
            return call_user_func_array([$model, $key], $args);
        } else {
            return null;
        }
    }