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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 smooth(self, n_iter=20, convergence=0.0, edge_angle=15, feature_angle=45, boundary_smoothing=True, feature_smoothing=False, inplace=False):
 """Adjust point coordinates using Laplacian smoothing. The effect is to "relax" the mesh, making the cells better shaped and the vertices more evenly distributed. Parameters n_iter : int Number of iterations for Laplacian smoothing, convergence : float, optional Convergence criterion for the iteration process. Smaller numbers result in more smoothing iterations. Range from (0 to 1). edge_angle : float, optional Edge angle to control smoothing along edges (either interior or boundary). feature_angle : float, optional Feature angle for sharp edge identification. boundary_smoothing : bool, optional Boolean flag to control smoothing of boundary edges. feature_smoothing : bool, optional Boolean flag to control smoothing of feature edges. inplace : bool, optional Updates mesh in-place while returning nothing. Returns ------- mesh : vtki.PolyData Decimated mesh. None when inplace=True. """

        alg = vtk.vtkSmoothPolyDataFilter()
        alg.SetInputData(self)
        alg.SetNumberOfIterations(n_iter)
        alg.SetConvergence(convergence)
        alg.SetFeatureEdgeSmoothing(feature_smoothing)
        alg.SetFeatureAngle(feature_angle)
        alg.SetEdgeAngle(edge_angle)
        alg.SetBoundarySmoothing(boundary_smoothing)
        alg.Update()

        mesh = _get_output(alg)
        if inplace:
            self.overwrite(mesh)
        else:
            return mesh