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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 edge_mask(self, angle):
 """ Returns a mask of the points of a surface mesh that have a surface angle greater than angle Parameters angle : float Angle to consider an edge. """

        self.point_arrays['point_ind'] = np.arange(self.n_points)
        featureEdges = vtk.vtkFeatureEdges()
        featureEdges.SetInputData(self)
        featureEdges.FeatureEdgesOn()
        featureEdges.BoundaryEdgesOff()
        featureEdges.NonManifoldEdgesOff()
        featureEdges.ManifoldEdgesOff()
        featureEdges.SetFeatureAngle(angle)
        featureEdges.Update()
        edges = _get_output(featureEdges)
        orig_id = vtki.point_scalar(edges, 'point_ind')

        return np.in1d(self.point_arrays['point_ind'], orig_id,
                       assume_unique=True)