code: def sync_map_items(self):
          
          if self._sync_map_items is None:
              self._sync_map_items = SyncMapItemList(
                  self._version,
                  service_sid=self._solution['service_sid'],
                  map_sid=self._solution['sid'],
              )
          return self._sync_map_items
docs: Access the sync_map_items
  
          :returns: twilio.rest.sync.v1.service.sync_map.sync_map_item.SyncMapItemList
          :rtype: twilio.rest.sync.v1.service.sync_map.sync_map_item.SyncMapItemList