code: def test_cast_observation(self):
      env = chainerrl.wrappers.CastObservationToFloat32(
          gym.make(self.env_id)
      )
  
      obs = env.reset()
      self.assertEqual(env.original_observation.dtype, np.float64)
      self.assertEqual(obs.dtype, np.float32)
      np.testing.assert_allclose(env.original_observation, obs)
  
      obs, r, done, info = env.step(env.action_space.sample())
      self.assertEqual(env.original_observation.dtype, np.float64)
      self.assertEqual(obs.dtype, np.float32)
      np.testing.assert_allclose(env.original_observation, obs)
  
file_path: chainerrl/tests/wrappers_tests/test_cast_observation.py
imports: import unittest
  from chainer import testing
  import gym
  import numpy
  import chainerrl
label_desc: Use image node_id 1 for calling the TestCastObservationToFloat32 obj's underlying member method code with example usage: obj.test_cast_observation() without return types