code: def testTermination(self):
      observation = tf.constant(-1)
      reward = tf.constant(2.0)
      time_step = ts.termination(observation, reward)
      time_step_ = self.evaluate(time_step)
      self.assertEqual(ts.StepType.LAST, time_step_.step_type)
      self.assertEqual(-1, time_step_.observation)
      self.assertEqual(2.0, time_step_.reward)
      self.assertEqual(0.0, time_step_.discount)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import sys
  import numpy
  import tensorflow
  from tf_agents.specs import array_spec
  from tf_agents.specs import tensor_spec
  from tf_agents.trajectories import time_step
  from tf_agents.utils import nest_utils
label_desc: Use image node_id 6 for calling the TFTimeStepTest obj's underlying member method code with example usage: obj.testTermination() without return types