I don't know how to solve this VTK Method error

I am using VTK in Python now. And This is the first time I have been programming with Python. After outputting the 3D object, we want to output the cross section of the object using the AddClippingPlane function. However, the following error will be displayed and it will not be executed:

TypeError: unbound method requires a vtkRenderingCorePython.vtkAbstractMapper as the first argument.

When you see the attached code, can you tell me what’s wrong? I would appreciate a lot your help.
Thank you

import vtk
import sys
from PyQt5 import QtCore,QtWidgets
from PyQt5.QtGui import  *
from vtk.qt.QVTKRenderWindowInteractor import QVTKRenderWindowInteractor
from PyQt5.QtWidgets import QMainWindow, QApplication
from foo import Ui_MainWindow
from PyQt5 import Qt

class MainWindow(QMainWindow, Ui_MainWindow):
    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)
        self.setMouseTracking(True)
        self.setupUi(self) 
        self.pushButton.clicked.connect(self.OpenVTK)     
        self.pushButton2.clicked.connect(
            QtCore.QCoreApplication.instance().quit)


    def OpenVTK(self):
        self.setMouseTracking(True)

        self.vtkWidget = QVTKRenderWindowInteractor(self.frame)
        self.vl = Qt.QVBoxLayout()
        self.vl.addWidget(self.vtkWidget)
        self.ren = vtk.vtkRenderer()
        self.vtkWidget.GetRenderWindow().AddRenderer(self.ren)
        self.iren = self.vtkWidget.GetRenderWindow().GetInteractor()

        reader = vtk.vtkDICOMImageReader()
        reader.SetDirectoryName(FilePath)

        reader.Update()
        colors = vtk.vtkNamedColors()
        colors.SetColor("BkgColor", [51, 77, 102, 255])
        boneExtractor = vtk.vtkMarchingCubes()
        boneExtractor.SetInputConnection(reader.GetOutputPort())
        boneExtractor.SetValue(0, 1000)
        boneStripper = vtk.vtkStripper()
        boneStripper.SetInputConnection(boneExtractor.GetOutputPort())
        boneMapper = vtk.vtkPolyDataMapper()
        boneMapper.SetInputConnection(boneStripper.GetOutputPort())
        boneMapper.ScalarVisibilityOff()
        plane1 = vtk.vtkPlane()
        plane1.SetOrigin(0.05, 0.0, 0.0)  # [*1]
        plane1.SetNormal(-1.0, 0.0, 0.0)

        bone = vtk.vtkActor()
        bone.SetMapper(boneMapper)
        bone.GetProperty().SetDiffuseColor(colors.GetColor3d("Ivory"))
        bone = vtk.vtkAbstractMapper.AddClippingPlane(plane1)

        bwLut = vtk.vtkLookupTable()
        bwLut.SetTableRange(0, 2000)
        bwLut.SetSaturationRange(0, 1)
        bwLut.SetHueRange(0, 0)
        bwLut.SetValueRange(0, 1)
        bwLut.Build() 

        sagittalColors = vtk.vtkImageMapToColors()
        sagittalColors.SetInputConnection(reader.GetOutputPort())
        sagittalColors.SetLookupTable(bwLut)
        sagittalColors.Update()

        sagittal = vtk.vtkImageActor()
        sagittal.GetMapper().SetInputConnection(sagittalColors.GetOutputPort())
        sagittal.SetDisplayExtent(250, 250, 0, 501, 0, 500) 

        aCamera = vtk.vtkCamera()
        aCamera.SetViewUp(0, 0, -1)
        aCamera.SetPosition(0, -1, 0)
        aCamera.SetFocalPoint(0, 0, 0)
        aCamera.ComputeViewPlaneNormal()
        aCamera.Azimuth(0.0)
        aCamera.Elevation(0.0)


        self.ren.AddActor(sagittal)
        self.ren.AddActor(bone)
        self.ren.SetActiveCamera(aCamera)
        self.show()
        self.ren.ResetCamera()
        self.frame.setLayout(self.vl)
        aCamera.Dolly(1.0)

        self.ren.ResetCameraClippingRange()
        self.show()
        self.iren.Initialize()
        self.iren.Start()


if __name__ == "__main__":
    app = QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec_())

Yes, vtkAbstractMapper is an abstract C++ class, which means it cannot be used directly, it must be used from an inherited class object.
Take a look at https://github.com/Kitware/VTK/blob/master/Examples/VolumeRendering/Python/VolumePicker.py

which has a use of AddClippingPlane with the volume mapper.

HTH,

Aron