code: def terminal_attribute_iterator(self, mapped_class=None, key=None):
          
          for attr in self._attribute_iterator(mapped_class, key):
              if attr.kind == RESOURCE_ATTRIBUTE_KINDS.TERMINAL:
                  yield attr
docs: Returns an iterator over all terminal mapped attributes for the given
          mapped class and attribute key. See :method:`get_attribute_map` for
          details.