docs: def get_model_indices(cls, index):
          '''
          Returns the list of model indices (i.e. ModelIndex objects) defined for this index.
          :param index: index name.
          '''
          try:
              return cls._idx_name_to_mdl_to_mdlidx[index].values()
          except KeyError:
              raise KeyError('Could not find any index named {}. Is this index defined in BUNGIESEARCH["INDICES"]?'.format(index))