code: def testTerminationIsLast(self):
      observation = -1
      reward = 2.0
      time_step = ts.termination(
          observation, reward
      )  # pytype: disable=wrong-arg-types
      self.assertTrue(time_step.is_last())
  
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 12 for calling the TimeStepTest obj's underlying member method code with example usage: obj.testTerminationIsLast() without return types