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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 mean_sdl(series, mult=2):
 """ mean plus or minus a constant times the standard deviation """

    m = series.mean()
    s = series.std()
    return pd.DataFrame({'y': [m],
                         'ymin': m-mult*s,
                         'ymax': m+mult*s})