def builddata(self, data):
raise NotImplementedError("<STR_LIT>")<EOL>
Extract fit data corresponding to this model from data set ``data``.

        The fit data is returned in a 1-dimensional array;
        the fitfcn must return arrays of the same length.

        Args:
            data: Data set containing the fit data for all models. This
                is typically a dictionary, whose keys are the ``datatag``\s
                of the models.