code: def _get_void_color(
      things: Set[int], stuffs: Set[int]
  ) -> Tuple[int, int]:
      """Get an unused color ID.
  
      Args:
          things: The set of category IDs for things.
          stuffs: The set of category IDs for stuffs.
  
      Returns:
          A new color ID that does not belong to things nor stuffs.
  
      """
      unused_category_id = 1 + max([0, *list(things), *list(stuffs)])
      return unused_category_id, 0
  
file_path: torchmetrics/src/torchmetrics/functional/detection/_panoptic_quality_common.py
imports: from typing import Collection, Dict, Iterator, List, Optional, Set, Tuple, cast
  import torch
  from torch import Tensor
  from torchmetrics.utilities import rank_zero_warn
label_desc: Use image node_id 6 for calling a global function with example usage: _get_void_color(things, stuffs) and returns: unused_category_id,  int