code: def normalize(self, reward):
      reward_threshold = np.percentile(self.buffer, self.percentile)
      if reward < reward_threshold:
          return -1.0
      else:
          return 1.0
  
file_path: ray/rllib_contrib/alpha_zero/src/rllib_alpha_zero/alpha_zero/ranked_rewards.py
imports: from copy import deepcopy
  import numpy
label_desc: Use image node_id 3 for calling the RankedRewardsBuffer obj's underlying member method code with example usage: obj.normalize(reward) and returns: unknown, int