class_docstr: Base class for Diet variable optimizers.
code: def __init__(self, params):
      self._params = params
      self._global_step = tf.train.get_or_create_global_step()
  
imports: from collections import defaultdict
  import copy
  import math
  from tensor2tensor.layers import common_layers
  from tensor2tensor.utils import hparam
  import tensorflow.compat.v1
label_desc: Use image node_id 1 to create a new DietVariableOptimizer object from inherited base classes: object with example: obj = DietVariableOptimizer(params)