code: def test_picklability(self):
      transform = AddBackgroundNoise(
          sounds_path=os.path.join(DEMO_DIR, "background_noises"), p=1.0
      )
      pickled = pickle.dumps(transform)
      unpickled = pickle.loads(pickled)
      assert transform.sound_file_paths == unpickled.sound_file_paths
  
file_path: audiomentations/tests/test_add_background_noise.py
imports: import json
  import os
  import pickle
  import random
  import warnings
  import numpy
  import pytest
  from audiomentations import AddBackgroundNoise, Compose, Reverse
  from demo.demo import DEMO_DIR
label_desc: Use image node_id 7 for calling the TestAddBackgroundNoise obj's underlying member method code with example usage: obj.test_picklability() without return types