code: def test_to_categorical_with_nb_classes_arg(self):
      vec = np.asarray([0])
      cat = np.asarray([[1, 0, 0]])
      self.assertTrue(np.all(utils.to_categorical(vec, 3) == cat))
  
file_path: cleverhans/cleverhans_v3.1.0/tests_tf/test_utils.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from __future__ import unicode_literals
  import unittest
  import numpy
  from cleverhans import utils
  from cleverhans.utils_keras import cnn_model
  from cleverhans.utils_keras import KerasModelWrapper
label_desc: Use image node_id 1 for calling the TestUtils obj's underlying member method code with example usage: obj.test_to_categorical_with_nb_classes_arg() without return types