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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 ema_growth(eqdata, **kwargs):
 """ Growth of exponential moving average. Parameters eqdata : DataFrame span : int, optional Span for exponential moving average. Defaults to 20. outputcol : str, optional. Column to use for output. Defaults to 'EMA Growth'. selection : str, optional Column of eqdata on which to calculate ema growth. If `eqdata` has only 1 column, `selection` is ignored, and ema growth is calculated on that column. Defaults to 'Adj Close'. Returns --------- out : DataFrame Growth of exponential moving average from one day to next """

    _growth_outputcol = kwargs.get('outputcol', 'EMA Growth')
    _ema_outputcol = 'EMA'
    kwargs['outputcol'] = _ema_outputcol
    _emadf = ema(eqdata, **kwargs)
    return simple.growth(_emadf, selection=_ema_outputcol, outputcol=_growth_outputcol)