code: def _build_test_env(obs_spec=None, action_spec=None, batch_size=2):
      if obs_spec is None:
          obs_spec = tensor_spec.BoundedTensorSpec(
              (2, 3), tf.int32, -10, 10
          )
      if action_spec is None:
          action_spec = tensor_spec.BoundedTensorSpec(
              (1,), tf.int32, 0, 4
          )
      time_step_spec = ts.time_step_spec(obs_spec)
      return random_tf_environment.RandomTFEnvironment(
          time_step_spec, action_spec, batch_size=batch_size
      )
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from absl.testing.absltest import mock
  import tensorflow
  from tf_agents.environments import random_tf_environment
  from tf_agents.environments import tf_wrappers
  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 1 for calling a global function with example usage: _build_test_env(obs_spec, action_spec, batch_size) and returns: random_tf_environment