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The SwimlaneBoundary element tool renders a rectangular border to show the bounding box of a
    bpmn2.Pool and bpmn2.HeaderedPool pool lane.
    It accepts the following arguments which can be passed as an object to the element tool constructor:
| laneId | string | Specifies the lane group for which the tool should be rendered. | 
|---|---|---|
| padding | number|object | Determines whether the boundary area should be visually inflated and if so, by how much. Default is 10({ left: 10, top: 10, right: 10, bottom: 10 }). | 
Example:
const boundaryTool = new joint.elementTools.SwimlaneBoundary({
    laneId: 'customLaneId',
    padding: 20
});