code: def testMixturePolicyChoices(self):
      context_dim = 34
      observation_spec = tensor_spec.TensorSpec(
          [context_dim], tf.float32
      )
      time_step_spec = ts.time_step_spec(observation_spec)
      action_spec = tensor_spec.BoundedTensorSpec(
          shape=(), dtype=tf.int32, minimum=0, maximum=9, name="action"
      )
      sub_policies = [
          ConstantPolicy(action_spec, time_step_spec, i)
          for i in range(10)
      ]
      weights = [0, 0, 0.2, 0, 0, 0.3, 0, 0, 0.5, 0]
      dist = tfd.Categorical(probs=weights)
      policy = mixture_policy.MixturePolicy(dist, sub_policies)
      batch_size = 15
      time_step = ts.TimeStep(
          tf.constant(
              ts.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(
              list(range(batch_size * context_dim)),
              dtype=tf.float32,
              shape=[batch_size, context_dim],
              name="observation",
          ),
      )
      action_step = policy.action(time_step)
      actions, infos = self.evaluate(
          [action_step.action, action_step.info]
      )
      tf.nest.assert_same_structure(policy.info_spec, infos)
      self.assertAllEqual(actions.shape, [batch_size])
      self.assertAllInSet(actions, [2, 5, 8])
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import os
  import tensorflow
  import tensorflow_probability
  from tf_agents.bandits.policies import mixture_policy
  from tf_agents.policies import policy_saver
  from tf_agents.policies import tf_policy
  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 2 for calling the MixturePolicyTest obj's underlying member method code with example usage: obj.testMixturePolicyChoices() without return types