class_docstr: similar to step but it allows non uniform steps defined by stepSizes
  
  
  :param step_size: the series of step sizes used for lr decay
  :param gamma: coefficient of decay
  
  
  >>> step = MultiStep([2, 5], 0.3)
  creating: createMultiStep
code: def get_scheduler(self) -> "optimizer.MultiStep":
      return self.scheduler
  
imports: from abc import ABC, abstractmethod
  from typing import List, Optional, TYPE_CHECKING
label_desc: Use image node_id 2 for calling the MultiStep obj's underlying member method code with example usage: obj.get_scheduler() and returns: self