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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 shrink(self, fraction=0.85):
 """Shrink the triangle polydata in the representation of the input mesh. Example: .. code-block:: python from vtkplotter import * pot = load(datadir + 'shapes/teapot.vtk').shrink(0.75) s = Sphere(r=0.2).pos(0,0,-0.5) show(pot, s) |shrink| |shrink.py|_ """

        poly = self.polydata(True)
        shrink = vtk.vtkShrinkPolyData()
        shrink.SetInputData(poly)
        shrink.SetShrinkFactor(fraction)
        shrink.Update()
        return self.updateMesh(shrink.GetOutput())