attr->is_editable = g_sheet_model_is_editable (sheet->model, row, col);
attr->is_visible = g_sheet_model_is_visible (sheet->model, row, col);
attr->is_editable = g_sheet_model_is_editable (sheet->model, row, col);
attr->is_visible = g_sheet_model_is_visible (sheet->model, row, col);