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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 cycle(cb, pool, params, plane):
 """ Fun function to do a palette cycling animation. :param cb: Cursebox instance. :type cb: cursebox.Cursebox :param params: Current application parameters. :type params: params.Params :param plane: Plane containing the current Mandelbrot values. :type plane: plane.Plane :return: """

    step = params.max_iterations // 20
    if step == 0:
        step = 1
    for i in range(0, params.max_iterations, step):
        params.palette_offset = i
        draw_panel(cb, pool, params, plane)
        cb.refresh()
    params.palette_offset = 0