code: def get_lr_func(lr_policy):
      """
      Given the configs, retrieve the specified lr policy function.
      Args:
          lr_policy (string): the learning rate policy to use for the job.
      """
      policy = "lr_func_" + lr_policy
      if policy not in globals():
          raise NotImplementedError(
              "Unknown LR policy: {}".format(lr_policy)
          )
      else:
          return globals()[policy]
  
imports: import math
label_desc: Use image node_id 5 for calling a global function with example usage: get_lr_func(lr_policy) and returns: globals