docstr: Test postprocess_trajectory
docstr_tok: ["Test","postprocess_trajectory"]
code: def test_torch_postprocess_trajectory(self):
      """Test postprocess_trajectory"""
      config = _default_config()
  
      observation_space = gym.spaces.Box(-1.0, 1.0, shape=(4,))
      action_space = gym.spaces.Box(-1.0, 1.0, shape=(3,))
  
      # Create policy
      policy = DTTorchPolicy(observation_space, action_space, config)
  
      # Generate input_dict with some data
      sample_batch = SampleBatch(
          {
              SampleBatch.REWARDS: np.array([1.0, 2.0, 1.0, 1.0]),
              SampleBatch.EPS_ID: np.array([0, 0, 0, 0]),
          }
      )
  
      # Do postprocess trajectory to calculate rtg.
      sample_batch = policy.postprocess_trajectory(sample_batch)
  
      # Assert that terminateds and truncateds are correctly set.
      assert (
          SampleBatch.TERMINATEDS in sample_batch
      ), "`terminateds` isn't part of the batch."
      assert (
          SampleBatch.TRUNCATEDS not in sample_batch
      ), "`truncateds` shouldn't be part of the batch (in this particular test case)."
      assert np.allclose(
          sample_batch[SampleBatch.TERMINATEDS],
          np.array([False, False, False, True]),
      ), "`terminateds` isn't set correctly."
  
file_path: ray/rllib_contrib/dt/tests/test_dt_policy.py
imports: import unittest
  from typing import Dict
  import gymnasium
  import numpy
  from rllib_dt.dt.dt_torch_policy import DTTorchPolicy
  import ray
  from ray.rllib.policy.sample_batch import SampleBatch
  from ray.rllib.utils.framework import try_import_tf, try_import_torch
label_desc: Use image node_id 3 for calling the TestDTPolicy obj's underlying member method code with example usage: obj.test_torch_postprocess_trajectory() without return types