code: def test_step(self):
      action_spec = tensor_spec.BoundedTensorSpec((), tf.int32, 0, 4)
      env = _build_test_env(action_spec=action_spec)
      mock_env = mock.Mock(wraps=env)
      wrapper = tf_wrappers.OneHotActionWrapper(mock_env)
      wrapper.reset()
  
      wrapper.step(
          tf.constant([[0, 1, 0, 0, 0], [0, 0, 0, 1, 0]], tf.int32)
      )
      self.assertTrue(mock_env.step.called)
      self.assertAllEqual([1, 3], mock_env.step.call_args[0][0])
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from absl.testing.absltest import mock
  import tensorflow
  from tf_agents.environments import random_tf_environment
  from tf_agents.environments import tf_wrappers
  from tf_agents.specs import tensor_spec
  from tf_agents.trajectories import time_step
  from tf_agents.utils import test_utils
label_desc: Use image node_id 4 for calling the OneHotActionWrapperTest obj's underlying member method code with example usage: obj.test_step() without return types