public static function check_X_y(\CArray $X, \CArray $y, bool $accept_sparse=false, bool $copy=False,
                                     bool $force_all_finite=True, bool $ensure_2d=True, bool $allow_nd=False,
                                     bool $multi_output=False, int $ensure_min_samples=1, int $ensure_min_features=1,
                                     bool $y_numeric=False, $estimator=null)
    {
        return [$X, $y];
    }