code: def __init__(self, env_config):
      super().__init__()
      self.state = None
      self.avail = env_config.get("avail_actions", [3])
      self.action_mask = np.array([0] * 10)
      for a in self.avail:
          self.action_mask[a] = 1
  
file_path: ray/rllib_contrib/qmix/tests/test_qmix.py
imports: import unittest
  import numpy
  from gymnasium.spaces import Box, Dict, Discrete, MultiDiscrete, Tuple
  from rllib_qmix.qmix import QMixConfig
  import ray
  from ray.rllib.env.multi_agent_env import MultiAgentEnv
  from ray.tune import register_env
label_desc: Use image node_id 1 to create a new AvailActionsTestEnv object from inherited base classes: MultiAgentEnv with example: obj = AvailActionsTestEnv(env_config)