code: def test_episode_reverse(self):
      from parlai.mutators.episode_reverse import EpisodeReverseMutator
  
      ex1, ex2, ex3, ex4 = self._apply_mutator(EpisodeReverseMutator)
  
      assert ex1["text"] == EXAMPLE2["text"]
      assert ex2["text"] == EXAMPLE1["text"]
      assert ex3["text"] == EXAMPLE4["text"]
      assert ex4["text"] == EXAMPLE3["text"]
      assert ex1["text"] == EXAMPLE2["text"]
  
imports: import unittest
  from parlai.core.params import ParlaiParser
  from parlai.core.opt import Opt
  from parlai.core.teachers import create_task_agent_from_taskname
  from parlai.core.message import Message
label_desc: Use image node_id 8 for calling the TestSpecificMutators obj's underlying member method code with example usage: obj.test_episode_reverse() without return types