code: function(key, opts) {
  			var node = this.getNodeByKey(key);
  			if (node) {
  				node.setActive(true, opts);
  			} else if (this.activeNode) {
  				this.activeNode.setActive(false, opts);
  			}
  			return node;
  		}
docs: Activate node with a given key and fire focus and activate events.
  
  A previously activated node will be deactivated.
  If activeVisible option is set, all parents will be expanded as necessary.
  Pass key = false, to deactivate the current node only.
  @param {string} key
  @param {object} [opts] additional options. Defaults to {noEvents: false, noFocus: false}
  @returns {FancytreeNode} activated node (null, if not found)