code: def test_load_openers_from_file(self):
      with NamedTemporaryFile() as tmpfile:
          tmpfile.write(b"hey\nhowdy")
          tmpfile.seek(0)
          op = load_openers_from_file(tmpfile.name)
      self.assertListEqual(op, ["hey", "howdy"])
  
file_path: ParlAI/tests/tasks/self_chat/test_worlds.py
imports: from parlai.agents.repeat_label.repeat_label import RepeatLabelAgent
  from parlai.core.worlds import create_task
  from parlai.scripts.display_data import setup_args
  from parlai.tasks.self_chat.worlds import load_openers_from_file, SelfChatWorld
  from tempfile import NamedTemporaryFile
  import unittest
  from unittest.mock import MagicMock
label_desc: Use image node_id 4 for calling the TestSelfChat obj's underlying member method code with example usage: obj.test_load_openers_from_file() without return types