docs: def repeat(self, rid, count, index=0):
          """
          Repeat an xml element marked with the matching rid.
          """
          elems = None
          if rid in self.__repeat_ids:
              elems = self.__repeat_ids[rid]
          elif rid in self.__element_ids:
              elems = self.__element_ids
  
          if elems and index < len(elems):
              elem = elems[index]
              self.__repeat(elem, count)