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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 simplify_spline(path, smooth=None, verbose=False):
 """ Replace discrete curves with b-spline or Arc and return the result as a new Path2D object. Parameters path : trimesh.path.Path2D Input geometry smooth : float Distance to smooth Returns simplified : Path2D Consists of Arc and BSpline entities """


    new_vertices = []
    new_entities = []
    scale = path.scale

    for discrete in path.discrete:
        circle = is_circle(discrete,
                           scale=scale,
                           verbose=verbose)
        if circle is not None:
            # the points are circular enough for our high standards
            # so replace them with a closed Arc entity
            new_entities.append(entities.Arc(points=np.arange(3) +
                                             len(new_vertices),
                                             closed=True))
            new_vertices.extend(circle)
            continue

        # entities for this path
        entity, vertices = points_to_spline_entity(discrete, smooth=smooth)
        # reindex returned control points
        entity.points += len(new_vertices)
        # save entity and vertices
        new_vertices.extend(vertices)
        new_entities.append(entity)

    # create the Path2D object for the result
    simplified = type(path)(entities=new_entities,
                            vertices=new_vertices)

    return simplified