code: def test_main_kwargs(self):
      opt = _TestScript.main(foo="test")
      assert opt.get("foo") == "test"
      assert opt.get("bar") == "sneaky"
  
imports: import sys
  import unittest
  from unittest.mock import patch
  from parlai.core.params import ParlaiParser
  import parlai.core.script
  import parlai.utils.testing
label_desc: Use image node_id 3 for calling the TestScriptRegistry obj's underlying member method code with example usage: obj.test_main_kwargs() without return types