code: def _get_initial_and_final_steps(batch_size, context_dim):
      observation = np.array(range(batch_size * context_dim)).reshape(
          [batch_size, context_dim]
      )
      initial_step = time_step.TimeStep(
          tf.constant(
              time_step.StepType.FIRST,
              dtype=tf.int32,
              shape=[batch_size],
              name="step_type",
          ),
          tf.constant(
              0.0, dtype=tf.float32, shape=[batch_size], name="reward"
          ),
          tf.constant(
              1.0, dtype=tf.float32, shape=[batch_size], name="discount"
          ),
          tf.constant(
              observation,
              dtype=tf.float32,
              shape=[batch_size, context_dim],
              name="observation",
          ),
      )
      final_step = time_step.TimeStep(
          tf.constant(
              time_step.StepType.LAST,
              dtype=tf.int32,
              shape=[batch_size],
              name="step_type",
          ),
          tf.constant(
              0.5, dtype=tf.float32, shape=[batch_size], name="reward"
          ),
          tf.constant(
              1.0, dtype=tf.float32, shape=[batch_size], name="discount"
          ),
          tf.constant(
              observation + 100.0,
              dtype=tf.float32,
              shape=[batch_size, context_dim],
              name="observation",
          ),
      )
      return initial_step, final_step
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from absl.testing import parameterized
  import numpy
  import tensorflow
  import tensorflow_probability
  from tf_agents.bandits.agents import exp3_mixture_agent
  from tf_agents.bandits.agents import lin_ucb_agent
  from tf_agents.bandits.drivers import driver_utils
  from tf_agents.bandits.policies import mixture_policy
  from tf_agents.policies import utils
  from tf_agents.specs import tensor_spec
  from tf_agents.trajectories import policy_step
  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: _get_initial_and_final_steps(batch_size, context_dim) and returns: initial_step,  final_step