The7 add widgets to 404 page

gistfile1.txt

add_action( 'get_header', 'dt_404_widget', 10 );

function dt_404_widget() {

	$config = Presscore_Config::get_instance();

	if( is_404() ) {
		$config->set( 'sidebar_position', 'right'  ); 
		$config->set( 'sidebar_widgetarea_id', 'sidebar_1' ); 
    		$config->set( 'footer_show', '1' ); 
		$config->set( 'footer_widgetarea_id', 'sidebar_2' );
	}
}