code: def test_audio_filter(fir_filter, art_warning, expected_values):
      try:
          # Load data for testing
          expected_data = expected_values()
  
          x1 = expected_data[0]
          x2 = expected_data[1]
          x3 = expected_data[2]
          result_0 = expected_data[3]
          result_1 = expected_data[4]
          result_2 = expected_data[5]
  
          # Create signal data
          x = np.array(
              [np.array(x1 * 2), np.array(x2 * 2), np.array(x3 * 2)],
              dtype=object,
          )
  
          # Filter params
          numerator_coef = np.array([0.1, 0.2, -0.1, -0.2])
  
          if fir_filter:
              denominator_coef = np.array([1.0])
          else:
              denominator_coef = np.array([1.0, 0.1, 0.3, 0.4])
  
          # Create filter
          audio_filter = LFilter(
              numerator_coef=numerator_coef,
              denominator_coef=denominator_coef,
          )
  
          # Apply filter
          result = audio_filter(x)
  
          # Test
          assert result[1] is None
          np.testing.assert_array_almost_equal(
              result_0, result[0][0], decimal=0
          )
          np.testing.assert_array_almost_equal(
              result_1, result[0][1], decimal=0
          )
          np.testing.assert_array_almost_equal(
              result_2, result[0][2], decimal=0
          )
  
      except ARTTestException as e:
          art_warning(e)
  
file_path: adversarial-robustness-toolbox/tests/preprocessing/audio/test_l_filter.py
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  import logging
  import numpy
  import pytest
  from art.preprocessing.audio import LFilter
  from tests.utils import ARTTestException
label_desc: Use image node_id 1 for calling a global function with example usage: test_audio_filter(fir_filter, art_warning, expected_values) without return types