code: def _reward(self):
      return -1 if (self.state != self.goal).any() else 0
  
file_path: coach/rl_coach/environments/toy_problems/bit_flip.py
imports: import random
  import gym
  import numpy
  from gym import spaces
label_desc: Use image node_id 3 for calling the BitFlip obj's underlying member method code with example usage: obj._reward() and returns: unknown