code: def test_inverse_gan(
      art_warning, fix_get_mnist_subset, image_dl_estimator_for_attack
  ):
      try:
          (
              x_train_mnist,
              y_train_mnist,
              x_test_mnist,
              y_test_mnist,
          ) = fix_get_mnist_subset
  
          gan, inverse_gan, sess = get_gan_inverse_gan_ft()
          if gan is None:
              logging.warning(
                  "Couldn't perform  this test because no gan is defined for this framework configuration"
              )
              return
  
          classifier = image_dl_estimator_for_attack(FastGradientMethod)
  
          attack = FastGradientMethod(classifier, eps=0.2)
          x_test_adv = attack.generate(x=x_test_mnist)
  
          inverse_gan = InverseGAN(
              sess=sess, gan=gan, inverse_gan=inverse_gan
          )
  
          x_test_defended = inverse_gan(x_test_adv, maxiter=1)
  
          np.testing.assert_array_almost_equal(
              float(np.mean(x_test_defended - x_test_adv)),
              0.08818667382001877,
              decimal=0.01,
          )
      except ARTTestException as e:
          art_warning(e)
  
file_path: adversarial-robustness-toolbox/tests/defences/preprocessor/test_inverse_gan.py
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  import pytest
  import logging
  import numpy
  from art.defences.preprocessor.inverse_gan import InverseGAN
  from art.attacks.evasion import FastGradientMethod
  from tests.utils import get_gan_inverse_gan_ft
  from tests.utils import ARTTestException
label_desc: Use image node_id 2 for calling a global function with example usage: test_inverse_gan(art_warning, fix_get_mnist_subset, image_dl_estimator_for_attack) without return types