code: def test_openai_retro(self):
      self.start_tests(name="openai-retro")
      self.unittest(
          environment=dict(
              environment="retro", level="Airstriker-Genesis"
          ),
          num_episodes=2,
      )
  
file_path: tensorforce/test/test_environments.py
imports: import pytest
  import unittest
  from test.unittest_base import UnittestBase
label_desc: Use image node_id 5 for calling the TestEnvironments obj's underlying member method code with example usage: obj.test_openai_retro() without return types