code: def test_group_agents_wrapper(self):
      MultiAgentCartPole = make_multi_agent("CartPole-v1")
      grouped_ma_cartpole = GroupAgentsWrapper(
          env=MultiAgentCartPole({"num_agents": 4}),
          groups={"group1": [0, 1], "group2": [2, 3]},
      )
      obs, _ = grouped_ma_cartpole.reset()
      self.assertTrue(len(obs) == 2)
      self.assertTrue("group1" in obs and "group2" in obs)
      self.assertTrue(
          isinstance(obs["group1"], list) and len(obs["group1"]) == 2
      )
      self.assertTrue(
          isinstance(obs["group2"], list) and len(obs["group2"]) == 2
      )
  
imports: import unittest
  from ray.rllib.env.wrappers.group_agents_wrapper import GroupAgentsWrapper
  from ray.rllib.env.multi_agent_env import make_multi_agent
label_desc: Use image node_id 1 for calling the TestGroupAgentsWrapper obj's underlying member method code with example usage: obj.test_group_agents_wrapper() without return types