class_docstr: Partially observable variant of the CartPole gym environment.
  
  https://github.com/openai/gym/blob/master/gym/envs/classic_control/
  cartpole.py
  
  We delete the x- and angular velocity components of the state, so that it
  can only be solved by a memory enhanced model (policy).
code: def __init__(self, config=None):
      super().__init__()
  
      # Fix our observation-space (remove 2 velocity components).
      high = np.array(
          [
              self.x_threshold * 2,
              self.theta_threshold_radians * 2,
          ],
          dtype=np.float32,
      )
  
      self.observation_space = Box(
          low=-high, high=high, dtype=np.float32
      )
  
file_path: ray/python/ray/rllib/examples/env/stateless_cartpole.py
imports: from gymnasium.spaces import Box
  import numpy
  from gymnasium.envs.classic_control import CartPoleEnv
label_desc: Use image node_id 1 to create a new StatelessCartPole object from inherited base classes: CartPoleEnv with example: obj = StatelessCartPole(config)