Error In use Guided Dragging

i want to use GuidedDraggingTool.js like this sample :
but when i drag a node i got this error in console :

TypeError: part.locationObject.getDocumentBounds is not a function

and drag never end, when i release mouse button ( mouseup ) drag did not end and node moving with mouse pointer.

here is my init code :

 myDiagram =
        GD(go.Diagram, "myDiagramDiv",  // must name or refer to the DIV HTML element
                draggingTool: new GuidedDraggingTool(),  // defined in GuidedDraggingTool.js
                "draggingTool.horizontalGuidelineColor": "blue",
                "draggingTool.verticalGuidelineColor": "blue",
                "draggingTool.centerGuidelineColor": "green",
                "draggingTool.guidelineWidth": 1,
                minScale: 0.25,
                grid: GD(go.Panel, "Grid",
                    GD(go.Shape, "LineH", { stroke: diagramStyle.GridLineHSmall_Color, strokeWidth: diagramStyle.GridLineHSmall_StrokeWidth }),
                    GD(go.Shape, "LineH", { stroke: diagramStyle.GridLineHLarge_Color, strokeWidth: diagramStyle.GridLineHLarge_StrokeWidth, interval: 10 }),
                    GD(go.Shape, "LineV", { stroke: diagramStyle.GridLineVSmall_Color, strokeWidth: diagramStyle.GridLineVSmall_StrokeWidth }),
                    GD(go.Shape, "LineV", { stroke: diagramStyle.GridLineVLarge_Color, strokeWidth: diagramStyle.GridLineVLarge_StrokeWidth, interval: 10 })
                initialContentAlignment: go.Spot.Center,
                initialDocumentSpot: go.Spot.TopCenter,
                initialViewportSpot: go.Spot.TopCenter,
                initialAutoScale: go.Diagram.Uniform,
                //allowDrop: true,  // must be true to accept drops from the Palette
                "LinkDrawn": showLinkLabel,  // this DiagramEvent listener is defined below
                "LinkRelinked": showLinkLabel,
                scrollsPageOnFocus: false,
                "undoManager.isEnabled": true  // enable undo & redo


That is a new method in version 2:

It appears that you are still using a version 1.* library.