code: def test_object_detection_data():
      df = ObjectDetectionDataset.from_voc(
          "https://autogluon.s3.amazonaws.com/datasets/tiny_motorbike.zip"
      )
      if df.is_packed():
          df2 = df.unpack().pack()
      else:
          df2 = df.pack().unpack()
      assert df2.equals(df), "pack unpack inconsistent"
  
imports: import os
  import tempfile
  import pandas
  from gluoncv.auto.data.dataset import ImageClassificationDataset
  from gluoncv.auto.data.dataset import ObjectDetectionDataset
label_desc: Use image node_id 2 for calling a global function with example usage: test_object_detection_data() without return types