code: def _setup_data(self):
      yield Message(EXAMPLE1)
      yield Message(EXAMPLE2)
      yield Message(EXAMPLE3)
      yield Message(EXAMPLE4)
  
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 1 for calling the TestSpecificMutators obj's underlying member method code with example usage: obj._setup_data() without return types