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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 validate_basic_smoother():
 """Run Friedman's test from Figure 2b."""

    x, y = sort_data(*smoother_friedman82.build_sample_smoother_problem_friedman82())
    plt.figure()
    # plt.plot(x, y, '.', label='Data')
    for span in smoother.DEFAULT_SPANS:
        my_smoother = smoother.perform_smooth(x, y, span)
        friedman_smooth, _resids = run_friedman_smooth(x, y, span)
        plt.plot(x, my_smoother.smooth_result, '.-', label='pyace span = {0}'.format(span))
        plt.plot(x, friedman_smooth, '.-', label='Friedman span = {0}'.format(span))
    finish_plot()