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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 cci(series, window=14):
 """ compute commodity channel index """

    price = typical_price(series)
    typical_mean = rolling_mean(price, window)
    res = (price - typical_mean) / (.015 * np.std(typical_mean))
    return pd.Series(index=series.index, data=res)