code: function(el) {
  				var widget;
  
  				if (el instanceof Fancytree) {
  					return el; // el already was a Fancytree
  				}
  				if (el === undefined) {
  					el = 0; // get first tree
  				}
  				if (typeof el === "number") {
  					el = $(".fancytree-container").eq(el); // el was an integer: return nth instance
  				} else if (typeof el === "string") {
  					el = $(el).eq(0); // el was a selector: use first match
  				} else if (el instanceof $) {
  					el = el.eq(0); // el was a jQuery object: use the first DOM element
  				} else if (el.originalEvent !== undefined) {
  					el = $(el.target); // el was an Event
  				}
  				el = el.closest(":ui-fancytree");
  				widget = el.data("ui-fancytree") || el.data("fancytree"); // the latter is required by jQuery <= 1.8
  				return widget ? widget.tree : null;
  			}
docs: Return a Fancytree instance, from element, index, event, or jQueryObject.
  
  @param {Element | jQueryObject | Event | integer | string} [el]
  @returns {Fancytree} matching tree or null
  @example
  $.ui.fancytree.getTree();   // Get first Fancytree instance on page
  $.ui.fancytree.getTree(1);  // Get second Fancytree instance on page
  $.ui.fancytree.getTree("#tree"); // Get tree for this matching element
  
  @since 2.13