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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 _output_cdf_plot(core_result, spid, models, options, fit_results):
 """Function for plotting cdf"""


    # CDF
    x = core_result['y'].values
    df = emp.empirical_cdf(x)
    df.columns = ['x', 'empirical']

    def calc_func(model, df, shapes):
        return eval("mod.%s.cdf(df['x'], *shapes)" % model)

    plot_exec_str = "ax.step(df['x'], emp, color='k', lw=3);ax.set_ylim(top=1)"

    _save_table_and_plot(spid, models, options, fit_results, 'data_pred_cdf',
                         df, calc_func, plot_exec_str)