code: def heuristic(env, s):
      """
      The heuristic for
      1. Testing
      2. Demonstration rollout.
  
      Args:
          env: The environment
          s (list): The state. Attributes:
              s[0] is the horizontal coordinate
              s[1] is the vertical coordinate
              s[2] is the horizontal speed
              s[3] is the vertical speed
              s[4] is the angle
              s[5] is the angular speed
              s[6] 1 if first leg has contact, else 0
              s[7] 1 if second leg has contact, else 0
  
      Returns:
           a: The heuristic to be fed into the step function defined above to determine the next step and reward.
      """
  
      angle_targ = (
          s[0] * 0.5 + s[2] * 1.0
      )  # angle should point towards center
      if angle_targ > 0.4:
          angle_targ = 0.4  # more than 0.4 radians (22 degrees) is bad
      if angle_targ < -0.4:
          angle_targ = -0.4
      hover_targ = 0.55 * np.abs(
          s[0]
      )  # target y should be proportional to horizontal offset
  
      angle_todo = (angle_targ - s[4]) * 0.5 - (s[5]) * 1.0
      hover_todo = (hover_targ - s[1]) * 0.5 - (s[3]) * 0.5
  
      if s[6] or s[7]:  # legs have contact
          angle_todo = 0
          hover_todo = (
              -(s[3]) * 0.5
          )  # override to reduce fall speed, that's all we need after contact
  
      if env.continuous:
          a = np.array([hover_todo * 20 - 1, -angle_todo * 20])
          a = np.clip(a, -1, +1)
      else:
          a = 0
          if hover_todo > np.abs(angle_todo) and hover_todo > 0.05:
              a = 2
          elif angle_todo < -0.05:
              a = 3
          elif angle_todo > +0.05:
              a = 1
      return a
  
imports: import math
  import warnings
  from typing import TYPE_CHECKING, Optional
  import numpy
  import gym
  from gym import error, spaces
  from gym.error import DependencyNotInstalled
  from gym.utils import EzPickle, colorize
  from gym.utils.step_api_compatibility import step_api_compatibility
label_desc: Use image node_id 1 for calling a global function with example usage: heuristic(env, s) and returns: a