code: def call(self, inputs, step_type=None, network_state=()):
      observations, actions = inputs
      del step_type
      observations = self._obs_layer(tf.nest.flatten(observations)[0])
      if self._shared_layer:
          observations = self._shared_layer(observations)
      actions = self._action_layer(tf.nest.flatten(actions)[0])
      joint = tf.concat([observations, actions], 1)
      q_value = self._joint_layer(joint)
      q_value = tf.reshape(q_value, [-1])
      return q_value, network_state
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import numpy
  import tensorflow
  from tf_agents.agents.td3 import td3_agent
  from tf_agents.networks import network
  from tf_agents.specs import tensor_spec
  from tf_agents.trajectories import policy_step
  from tf_agents.trajectories import time_step
  from tf_agents.trajectories import trajectory
  from tf_agents.utils import common
  from tf_agents.utils import test_utils
label_desc: Use image node_id 2 for calling the DummyCriticNetwork obj's underlying member method code with example usage: obj.call(inputs, step_type, network_state) and returns: q_value,  network_state