How to use the jsplumb.getSelector function in jsplumb

function _attach_node_draggable(sel){

	var foo = jsPlumb.getSelector(sel);

	// Make it draggable, and update where it is when it is
	// dropped.
	function _on_drag_stop(evt, ui){

	    // Try an jimmy out the enode ssociated with this event.
	    var enid = ui.helper.attr('id');
	    var en = ecore.get_node_by_elt_id(enid);

	    // If we got something, locate it and save the position.
	    if( en ){

		// Grab position.
		var t = ui.position.top;
		var l = ui.position.left;

function _make_selector_source(sel, subsel){
        instance.makeSource(jsPlumb.getSelector(sel), {
            filter: subsel,
            anchor:"Continuous",
	    isSource: true,
	    //maxConnections: -1,
            connector:[ "Sugiyama", { curviness: 25 } ]
        });
    }

function _make_selector_target(sel){
	instance.makeTarget(jsPlumb.getSelector(sel), {
    	    anchor:"Continuous",
	    isTarget: true,
	    //maxConnections: -1,
	    connector:[ "Sugiyama", { curviness: 25 } ]
    	});
    }