def deserialize(self, body):
        raise NotImplementedError("Subclasses must implement this method.")
second derivative of transf(f) w.r.t. f
dataset/ETHPy150Open tgonzales/mingus/mingus/serializers.py/Serializer.deserialize--crossover with--dataset/ETHPy150Open SheffieldML/GPy/GPy/likelihoods/link_functions.py/GPTransformation.d2transf_df2