code: def healthy_reward(self):
      return (
          float(self.is_healthy or self._terminate_when_unhealthy)
          * self._healthy_reward
      )
  
file_path: gym/gym/envs/mujoco/walker2d_v3.py
imports: import numpy
  from gym import utils
  from gym.envs.mujoco import MuJocoPyEnv
  from gym.spaces import Box
label_desc: Use image node_id 2 for calling the Walker2dEnv obj's underlying member method code with example usage: obj.healthy_reward() and returns: unknown