class_docstr: Mock for TrainedAttacker.
class_docstr_tok: ["Mock","for","TrainedAttacker","."]
code: def predict(self, input_features):
      return input_features[:, 0]
  
imports: from unittest import mock
  from absl.testing import absltest
  from absl.testing import parameterized
  import numpy
  from tensorflow_privacy.privacy.privacy_tests import epsilon_lower_bound
  from tensorflow_privacy.privacy.privacy_tests.membership_inference_attack import membership_inference_attack
  from tensorflow_privacy.privacy.privacy_tests.membership_inference_attack import models
  from tensorflow_privacy.privacy.privacy_tests.membership_inference_attack.data_structures import AttackInputData
  from tensorflow_privacy.privacy.privacy_tests.membership_inference_attack.data_structures import AttackType
  from tensorflow_privacy.privacy.privacy_tests.membership_inference_attack.data_structures import DataSize
  from tensorflow_privacy.privacy.privacy_tests.membership_inference_attack.data_structures import SingleSliceSpec
  from tensorflow_privacy.privacy.privacy_tests.membership_inference_attack.data_structures import SlicingFeature
  from tensorflow_privacy.privacy.privacy_tests.membership_inference_attack.data_structures import SlicingSpec
label_desc: Use image node_id 3 for calling the MockTrainedAttacker obj's underlying member method code with example usage: obj.predict(input_features) and returns: input_features