code: def test_evaluate_defense(self):
      # Get MNIST
      (x_train, _), (_, _), (_, _) = self.mnist
  
      kwargs = {"nb_clusters": 2, "nb_dims": 10, "reduce": "PCA"}
      _, _ = self.defence.detect_poison(**kwargs)
      _, _ = self.defence_gen.detect_poison(**kwargs)
      is_clean = np.zeros(len(x_train))
      self.defence.evaluate_defence(is_clean)
      self.defence_gen.evaluate_defence(is_clean)
  
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  import logging
  import unittest
  from keras.preprocessing.image import ImageDataGenerator
  import numpy
  from art.data_generators import KerasDataGenerator
  from art.defences.detector.poison import ActivationDefence
  from art.utils import load_mnist
  from art.visualization import convert_to_rgb
  from tests.utils import master_seed
label_desc: Use image node_id 11 for calling the TestActivationDefence obj's underlying member method code with example usage: obj.test_evaluate_defense() without return types