to_blocks example

// Set up the $menu_item variables.         // Adds the class property classes for the current context, if applicable.         _wp_menu_item_classes_by_context( $menu_items );

        $menu_items_by_parent_id = static::group_by_parent_id( $menu_items );

        $first_menu_item = isset( $menu_items_by_parent_id[0] )
            ? $menu_items_by_parent_id[0]
            : array();

        $inner_blocks = static::to_blocks(
            $first_menu_item,
            $menu_items_by_parent_id
        );

        return serialize_blocks( $inner_blocks );
    }

    /** * Returns an array of menu items grouped by the id of the parent menu item. * * @since 6.3.0 * * @param array $menu_items An array of menu items. * @return array */