code: def update_step(self, gradient, variable, learning_rate):
      raise NotImplementedError
  
imports: import re
  import warnings
  import numpy
  from keras import backend
  from keras import initializers
  from keras import ops
  from keras.optimizers.schedules import learning_rate_schedule
  from keras.saving import serialization_lib
  from keras.utils import tracking
  from keras.utils.naming import auto_name
label_desc: Use image node_id 13 for calling the BaseOptimizer obj's underlying member method code with example usage: obj.update_step(gradient, variable, learning_rate) without return types