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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 ln_growth(eqdata, **kwargs):
 """ Return the natural log of growth. See also -------- :func:`growth` """

    if 'outputcol' not in kwargs:
        kwargs['outputcol'] = 'LnGrowth'
    return np.log(growth(eqdata, **kwargs))