def modify_state_for_body(s, body):
            s.layers['segmentation'].segments = frozenset([body.segment_id])
            s.voxel_coordinates = body.bbox_start + body.bbox_size // 2
def add_item(self, item_value=None, index=None):
    if item_value is None:
      item_value = self._new_item_default_value