class_docstr: Corridor in which an agent must learn to move right to reach the exit.
  
  ---------------------
  | S | 1 | 2 | 3 | G |   S=start; G=goal; corridor_length=5
  ---------------------
  
  Possible actions to chose from are: 0=left; 1=right
  Observations are floats indicating the current field index, e.g. 0.0 for
  starting position, 1.0 for the field next to the starting position, etc..
  Rewards are -0.1 for all steps, except when reaching the goal (+1.0).
code: def __init__(self, config):
      self.end_pos = config["corridor_length"]
      self.cur_pos = 0
      self.action_space = gym.spaces.Discrete(2)  # left and right
      self.observation_space = gym.spaces.Box(
          0.0, self.end_pos, shape=(1,)
      )
  
imports: import gymnasium
  from ray.rllib.algorithms.ppo import PPOConfig
label_desc: Use image node_id 1 to create a new SimpleCorridor object from inherited base classes: gym with example: obj = SimpleCorridor(config)