class_docstr: HalfCheetah Environment with two diff tasks, moving forwards or backwards
  
  Direction is defined as a scalar: +1.0 (forwards) or -1.0 (backwards)
code: def __init__(self, goal_direction=None):
      self.goal_direction = goal_direction if goal_direction else 1.0
      MujocoEnv.__init__(self, "half_cheetah.xml", 5)
      EzPickle.__init__(self, goal_direction)
  
file_path: ray/rllib/examples/env/halfcheetah_rand_direc.py
imports: from gymnasium.envs.mujoco.mujoco_env import MujocoEnv
  from gymnasium.utils import EzPickle
  import numpy
  from ray.rllib.env.apis.task_settable_env import TaskSettableEnv
label_desc: Use image node_id 1 to create a new HalfCheetahRandDirecEnv object from inherited base classes: MujocoEnv, EzPickle, TaskSettableEnv with example: obj = HalfCheetahRandDirecEnv(goal_direction)