code: def _episode_reward(env):
      timestep = env.reset()
      action_spec = env.action_spec()
      rng = np.random.RandomState(seed=1)
      reward = []
      while not timestep.last():
          timestep = env.step(rng.randint(action_spec.num_values))
          reward.append(timestep.reward)
      return reward
  
file_path: acme/acme/wrappers/delayed_reward_test.py
imports: from typing import Any
  from acme import wrappers
  from acme.testing import fakes
  from dm_env import specs
  import numpy
  import tree
  from absl.testing import absltest
  from absl.testing import parameterized
label_desc: Use image node_id 1 for calling a global function with example usage: _episode_reward(env) and returns: reward