docs: def growth_volatility(eqdata, **kwargs):
      """
      Return the volatility of growth.
  
      Note that, like :func:`pynance.tech.simple.growth` but in contrast to 
      :func:`volatility`, :func:`growth_volatility`
      applies directly to a dataframe like that returned by 
      :func:`pynance.data.retrieve.get`, not necessarily to a single-column dataframe.
  
      Parameters
      ----------
      eqdata : DataFrame
          Data from which to extract growth volatility. An exception
          will be raised if `eqdata` does not contain a column 'Adj Close'
          or an optional name specified by the `selection` parameter.
      window : int, optional
          Window on which to calculate volatility. Defaults to 20.
      selection : str, optional
          Column of eqdata on which to calculate volatility of growth. Defaults
          to 'Adj Close'
      outputcol : str, optional
          Column to use for output. Defaults to 'Growth Risk'.
  
      Returns
      ---------
      out : DataFrame
          Dataframe showing the volatility of growth over the specified `window`.
      """
      _window = kwargs.get('window', 20)
      _selection = kwargs.get('selection', 'Adj Close')
      _outputcol = kwargs.get('outputcol', 'Growth Risk')
      _growthdata = simple.growth(eqdata, selection=_selection)
      return volatility(_growthdata, outputcol=_outputcol, window=_window)