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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 ratio_to_delta(self, isos_ss, ratio, oneover=False):
        '''
        Transforms an isotope ratio into a delta value

        Parameters
        ----------
        isos_ss: list or float
            list w/ isotopes, e.g., ['N-14','N-15'] OR the solar
            system ratio.
        ratio : float
            ratio of the isotopes to transform.
        oneover : boolean
            take the inverse of the ratio before transforming (never
            inverse of delta value!).  The default is False.

        Returns
        -------
        float
            delta value

        '''
        # define if isos_ss is the ratio or the isotopes
        if type(isos_ss) == float:
            ss_ratio = isos_ss
        elif type(isos_ss) == list:
            ss_ratio = self.inut.isoratio_init(isos_ss)
        else:
            print('Check input of isos_ss into ratio_to_delta routine')
            return None

        # check if one over is necessary or not
        if oneover:
            ratio = old_div(1,ratio)

        # calculate delta value
        delta = (old_div(ratio, ss_ratio) - 1.) * 1000.

        return delta