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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 log(x, base=None):
 """ Calculate the log Parameters x : float or array_like Input values base : int or float (Default: None) Base of the log. If `None`, the natural logarithm is computed (`base=np.e`). Returns ------- out : float or ndarray Calculated result """

    if base == 10:
        return np.log10(x)
    elif base == 2:
        return np.log2(x)
    elif base is None or base == np.e:
        return np.log(x)
    else:
        return np.log(x)/np.log(base)