docs: def prior_class_dict(self):
          """
          Returns
          -------
          prior_class_dict: {Prior: class}
              A dictionary mapping Priors to associated classes. Each prior will only have one class; if a prior is
              shared by two classes then only one of those classes will be in this dictionary.
          """
          return {prior: cls
                  for prior_model_tuple in self.prior_model_tuples
                  for prior, cls in
                  prior_model_tuple.prior_model.prior_class_dict.items()}