code: def test_get_label_map_pascal_voc(self):
      pascal_dir = tasks_test_utils.get_test_data_path(
          "pascal_voc_data"
      )
      label_map = dataset_util.get_label_map_pascal_voc(pascal_dir)
      all_keys = sorted(label_map.keys())
      self.assertEqual(label_map[0], "background")
      self.assertEqual(all_keys[0], 0)
      self.assertEqual(all_keys[-1], 2)
      self.assertLen(all_keys, 3)
  
imports: import hashlib
  import json
  import os
  import shutil
  from unittest import mock
  import tensorflow
  from mediapipe.model_maker.python.vision.core import test_utils
  from mediapipe.model_maker.python.vision.object_detector import dataset_util
  from mediapipe.tasks.python.test import test_utils
label_desc: Use image node_id 12 for calling the DatasetUtilTest obj's underlying member method code with example usage: obj.test_get_label_map_pascal_voc() without return types