class_docstr: Set the parameter by a function of epoch num and old value. 
code: def _get_value_to_set(self):
      return self.f(self.epoch_num, self.get_current_value())
  
imports: import operator
  import os
  import numpy
  from abc import ABCMeta, abstractmethod
  from collections import deque
  import six
  from ..compat import tfv1
  from ..tfutils.common import get_op_tensor_name
  from ..utils import logger
  from .base import Callback
label_desc: Use image node_id 2 for calling the HyperParamSetterWithFunc obj's underlying member method code with example usage: obj._get_value_to_set() and returns: self