code: def initial_state(self, batch_size):
      return ()
  
file_path: acme/acme/tf/networks/recurrence_test.py
imports: import os
  from acme import specs
  from acme.tf import savers
  from acme.tf import utils
  from acme.tf.networks import recurrence
  import numpy
  import sonnet
  import tensorflow
  import tree
  from absl.testing import absltest
label_desc: Use image node_id 2 for calling the RNNCritic obj's underlying member method code with example usage: obj.initial_state(batch_size) and returns: 