code: def test_nested_dicts_ravel(self, observation_space, flat_shape):
      env = FakeEnvironment(observation_space=observation_space)
      wrapped_env = FlattenObservation(
          FilterObservation(env, env.obs_keys)
      )
      obs, info = wrapped_env.reset()
      assert obs.shape == wrapped_env.observation_space.shape
      assert isinstance(info, dict)
  
file_path: gym/tests/wrappers/test_nested_dict.py
imports: from typing import Optional
  import numpy
  import pytest
  import gym
  from gym.spaces import Box, Dict, Tuple
  from gym.wrappers import FilterObservation, FlattenObservation
label_desc: Use image node_id 2 for calling the TestNestedDictWrapper obj's underlying member method code with example usage: obj.test_nested_dicts_ravel(observation_space, flat_shape) without return types