docstr: Bin reward to {+1, 0, -1} by its sign.
docstr_tok: ["Bin","reward","to","{","+1",",","0",",","-1","}","by","its","sign","."]
code: def reward(self, reward):
      """Bin reward to {+1, 0, -1} by its sign."""
      return np.sign(reward)
  
imports: import time
  import numpy
  from collections import deque
  import gym
  from gym import spaces
  from parl.env.compat_wrappers import CompatWrapper, is_gym_version_ge, V_NPRANDOM_CHANGED
  import cv2
label_desc: Use image node_id 4 for calling the ClipRewardEnv obj's underlying member method code with example usage: obj.reward(reward) and returns: np