class_docstr: Coin Game environment.
code: def _generate_observation(self):
      obs = np.zeros((self.grid_size, self.grid_size, 4))
      obs[self.red_pos[0], self.red_pos[1], 0] = 1
      obs[self.blue_pos[0], self.blue_pos[1], 1] = 1
      if self.red_coin:
          obs[self.coin_pos[0], self.coin_pos[1], 2] = 1
      else:
          obs[self.coin_pos[0], self.coin_pos[1], 3] = 1
  
      obs = self._get_obs_invariant_to_the_player_trained(obs)
  
      return obs
  
imports: import copy
  import gymnasium
  import logging
  import numpy
  from gymnasium.spaces import Discrete
  from gymnasium.utils import seeding
  from ray.rllib.env.multi_agent_env import MultiAgentEnv
  from ray.rllib.utils import override
  from typing import Dict, Optional
  from ray.rllib.examples.env.utils.interfaces import InfoAccumulationInterface
label_desc: Use image node_id 10 for calling the CoinGame obj's underlying member method code with example usage: obj._generate_observation() and returns: obs