code: def test_convai2(self):
      SelfChat.main(
          task="convai2",
          model="fixed_response",
          fixed_response="hi",
          dt="valid",
      )
  
file_path: ParlAI/tests/test_self_chat.py
imports: from tempfile import NamedTemporaryFile
  import unittest
  from parlai.scripts.self_chat import SelfChat
  import parlai.utils.testing
label_desc: Use image node_id 2 for calling the TestSelfChat obj's underlying member method code with example usage: obj.test_convai2() without return types