code: def metadata(self):
      return MetadataCatalog.get("coco_2017_train")
  
imports: import numpy
  import os
  import tempfile
  import unittest
  import cv2
  import torch
  from detectron2.data import MetadataCatalog
  from detectron2.structures import BoxMode, Instances, RotatedBoxes
  from detectron2.utils.visualizer import ColorMode, Visualizer
label_desc: Use image node_id 2 for calling the TestVisualizer obj's underlying member method code with example usage: obj.metadata() and returns: MetadataCatalog