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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 from_center_of_mass(cls, inputs, window_length, center_of_mass, **kwargs):
 """ Convenience constructor for passing `decay_rate` in terms of center of mass. Forwards `decay_rate` as `1 - (1 / 1 + center_of_mass)`. This provides behavior equivalent to passing `center_of_mass` to pandas.ewma. Examples -------- .. code-block:: python # Equivalent to: # my_ewma = EWMA( # inputs=[EquityPricing.close], # window_length=30, # decay_rate=(1 - (1 / 15.0)), # ) my_ewma = EWMA.from_center_of_mass( inputs=[EquityPricing.close], window_length=30, center_of_mass=15, ) Notes ----- This classmethod is provided by both :class:`ExponentialWeightedMovingAverage` and :class:`ExponentialWeightedMovingStdDev`. """

        return cls(
            inputs=inputs,
            window_length=window_length,
            decay_rate=(1.0 - (1.0 / (1.0 + center_of_mass))),
            **kwargs
        )