code: def identity_epsilon(
      unused_decay_period, unused_step, unused_warmup_steps, epsilon
  ):
      return epsilon
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import math
  import os
  import random
  from absl import logging
  from dopamine.discrete_domains import atari_lib
  from dopamine.replay_memory import circular_replay_buffer
  import gin.tf
  import numpy
  import tensorflow
label_desc: Use image node_id 2 for calling a global function with example usage: identity_epsilon(unused_decay_period, unused_step, unused_warmup_steps, epsilon) and returns: epsilon