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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 decimate_pro(self, reduction, feature_angle=45.0, split_angle=75.0, splitting=True, pre_split_mesh=False, preserve_topology=False, inplace=False):
 """Reduce the number of triangles in a triangular mesh, forming a good approximation to the original geometry. Based on the algorithm originally described in "Decimation of Triangle Meshes", Proc Siggraph `92. Parameters reduction : float Reduction factor. A value of 0.9 will leave 10 % of the original number of vertices. feature_angle : float, optional Angle used to define what an edge is (i.e., if the surface normal between two adjacent triangles is >= feature_angle, an edge exists). split_angle : float, optional Angle used to control the splitting of the mesh. A split line exists when the surface normals between two edge connected triangles are >= split_angle. splitting : bool, optional Controls the splitting of the mesh at corners, along edges, at non-manifold points, or anywhere else a split is required. Turning splitting off will better preserve the original topology of the mesh, but may not necessarily give the exact requested decimation. pre_split_mesh : bool, optional Separates the mesh into semi-planar patches, which are disconnected from each other. This can give superior results in some cases. If pre_split_mesh is set to True, the mesh is split with the specified split_angle. Otherwise mesh splitting is deferred as long as possible. preserve_topology : bool, optional Controls topology preservation. If on, mesh splitting and hole elimination will not occur. This may limit the maximum reduction that may be achieved. inplace : bool, optional Updates mesh in-place while returning nothing. Returns ------- mesh : vtki.PolyData Decimated mesh. None when inplace=True. """


        alg = vtk.vtkDecimatePro()
        alg.SetInputData(self)
        alg.SetTargetReduction(reduction)
        alg.SetPreserveTopology(preserve_topology)
        alg.SetFeatureAngle(feature_angle)
        alg.SetSplitting(splitting)
        alg.SetSplitAngle(split_angle)
        alg.SetPreSplitMesh(pre_split_mesh)
        alg.Update()

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