code: def test_observation_space(self):
      self.assertEqual(
          self.vec_env.observation_space, self.envs[0].observation_space
      )
  
file_path: chainerrl/tests/envs_tests/test_vector_envs.py
imports: import unittest
  from chainer import testing
  import gym
  import numpy
  import chainerrl
label_desc: Use image node_id 5 for calling the TestSerialVectorEnv obj's underlying member method code with example usage: obj.test_observation_space() without return types