code: def test_InsertInBackground(self):
      self.evaluate_class(
          vidaugs.InsertInBackground(offset_factor=0.25),
          fname="insert_in_background",
          metadata_exclude_keys=[
              "dst_duration",
              "dst_fps",
              "intensity",
              "local_path",
          ],
      )
  
imports: import json
  import random
  import unittest
  from augly import audio, video
  from augly.tests.base_configs import VideoAugConfig
  from augly.tests.video_tests.base_unit_test import BaseVideoUnitTest
  from augly.utils import VIDEO_METADATA_PATH
  from augly.utils.ffmpeg import get_conditional_for_skipping_video_tests
label_desc: Use image node_id 4 for calling the TransformsVideoUnitTest obj's underlying member method code with example usage: obj.test_InsertInBackground() without return types