code: def test_context_shuffle(self):
      from parlai.mutators.context_shuffle import ContextShuffleMutator
  
      ex1, ex2, ex3, ex4 = self._apply_context_mutator(
          ContextShuffleMutator
      )
  
      ex1_lines = ex1["text"].split("\n")
      assert len(ex1_lines) == 3
      assert sorted(ex1_lines) == sorted(
          CONTEXT.split("\n") + [EXAMPLE1["text"]]
      )
      ex3_lines = ex3["text"].split("\n")
      assert len(ex3_lines) == 3
      assert sorted(ex3_lines) == sorted(
          CONTEXT.split("\n") + [EXAMPLE3["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 7 for calling the TestSpecificMutators obj's underlying member method code with example usage: obj.test_context_shuffle() without return types