code: def get_delta_gradients(self):
      # logger.info(f"gradient: {self.model_parameter.grad}, prev model parameter: {self.prev_model_parameter},"
      # f"delta grad: {self.prev_model_parameter.data - self.model_parameter.data}")
      if self.prev_model_parameter is not None:
          return (
              self.prev_model_parameter.data - self.model_parameter.data
          )
      else:
          raise ValueError(
              f"No optimization history found, please check."
          )
  
imports: import logging
  import numpy
  import torch
label_desc: Use image node_id 4 for calling the Optimizer obj's underlying member method code with example usage: obj.get_delta_gradients() and returns: unknown