code: def testRaiseValueErrorWithoutSession(self):
      if tf.executing_eagerly():
          self.skipTest(
              "b/123770140: Handling sessions with eager mode is buggy"
          )
      policy = py_tf_policy.PyTFPolicy(self._tf_policy)
      with self.assertRaisesRegexp(
          AttributeError,
          "No TensorFlow session-like object was set on this 'PyTFPolicy'.*",
      ):
          policy.get_initial_state()
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import os
  from absl import flags
  from absl.testing import parameterized
  import numpy
  import tensorflow
  from tf_agents.networks import network
  from tf_agents.policies import actor_policy
  from tf_agents.policies import ou_noise_policy
  from tf_agents.policies import py_tf_policy
  from tf_agents.policies import q_policy
  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 3 for calling the PyTFPolicyTest obj's underlying member method code with example usage: obj.testRaiseValueErrorWithoutSession() without return types