code: def bbox2fields():
      """The key correspondence from bboxes to labels, masks and
      segmentations."""
      bbox2label = {
          "gt_bboxes": "gt_labels",
          "gt_bboxes_ignore": "gt_labels_ignore",
      }
      bbox2mask = {
          "gt_bboxes": "gt_masks",
          "gt_bboxes_ignore": "gt_masks_ignore",
      }
      bbox2seg = {
          "gt_bboxes": "gt_semantic_seg",
      }
      return bbox2label, bbox2mask, bbox2seg
  
imports: import copy
  import cv2
  import mmcv
  import numpy
  from ..builder import PIPELINES
  from .compose import Compose
label_desc: Use image node_id 4 for calling a global function with example usage: bbox2fields() and returns: bbox2label,  bbox2mask,  bbox2seg