docs: def get_model_index(cls, model, default=True):
          '''
          Returns the default model index for the given model, or the list of indices if default is False.
          :param model: model name as a string.
          :raise KeyError: If the provided model does not have any index associated.
          '''
          try:
              if default:
                  return cls._model_name_to_default_index[model]
              return cls._model_name_to_model_idx[model]
          except KeyError:
              raise KeyError('Could not find any model index defined for model {}.'.format(model))