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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def export_flow_di_data(params, plane):
 """ Creates a new BPMNEdge XML element for given edge parameters and adds it to 'plane' element. :param params: dictionary with edge parameters, :param plane: object of Element class, representing BPMN XML 'BPMNPlane' element (root for edge DI data). """

        output_flow = eTree.SubElement(plane, BpmnDiagramGraphExport.bpmndi_namespace + consts.Consts.bpmn_edge)
        output_flow.set(consts.Consts.id, params[consts.Consts.id] + "_gui")
        output_flow.set(consts.Consts.bpmn_element, params[consts.Consts.id])
        waypoints = params[consts.Consts.waypoints]
        for waypoint in waypoints:
            waypoint_element = eTree.SubElement(output_flow, "omgdi:waypoint")
            waypoint_element.set(consts.Consts.x, waypoint[0])
            waypoint_element.set(consts.Consts.y, waypoint[1])