code: def testObservationSpec(self):
      py_env = PYEnvironmentMock()
      tf_env = tf_py_environment.TFPyEnvironment(py_env)
      spec = tf_env.observation_spec()
      self.assertEqual(type(spec), specs.TensorSpec)
      self.assertEqual(spec.dtype, tf.int64)
      self.assertEqual(spec.shape, tf.TensorShape([]))
      self.assertEqual(spec.name, "observation")
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import threading
  from typing import Text
  from absl.testing import parameterized
  from absl.testing.absltest import mock
  import numpy
  import tensorflow
  from tf_agents import specs
  from tf_agents.environments import batched_py_environment
  from tf_agents.environments import py_environment
  from tf_agents.environments import suite_gym
  from tf_agents.environments import tf_py_environment
  from tf_agents.trajectories import time_step
  from tf_agents.utils import common
label_desc: Use image node_id 5 for calling the TFPYEnvironmentTest obj's underlying member method code with example usage: obj.testObservationSpec() without return types