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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 smoothLaplacian(self, niter=15, relaxfact=0.1, edgeAngle=15, featureAngle=60):
 """ Adjust mesh point positions using `Laplacian` smoothing. :param int niter: number of iterations. :param float relaxfact: relaxation factor. Small `relaxfact` and large `niter` are more stable. :param float edgeAngle: edge angle to control smoothing along edges (either interior or boundary). :param float featureAngle: specifies the feature angle for sharp edge identification. .. hint:: |mesh_smoothers.py|_ """

        poly = self.poly
        cl = vtk.vtkCleanPolyData()
        cl.SetInputData(poly)
        cl.Update()
        smoothFilter = vtk.vtkSmoothPolyDataFilter()
        smoothFilter.SetInputData(cl.GetOutput())
        smoothFilter.SetNumberOfIterations(niter)
        smoothFilter.SetRelaxationFactor(relaxfact)
        smoothFilter.SetEdgeAngle(edgeAngle)
        smoothFilter.SetFeatureAngle(featureAngle)
        smoothFilter.BoundarySmoothingOn()
        smoothFilter.FeatureEdgeSmoothingOn()
        smoothFilter.GenerateErrorScalarsOn()
        smoothFilter.Update()
        return self.updateMesh(smoothFilter.GetOutput())