code: def _update_nesterov_momentum_numpy(
      self, var, accum, g, lr, momentum
  ):
      var = var + accum * lr * momentum
      accum = accum * momentum + g
      var = var - lr * accum
      var = var - accum * lr * momentum
      return var, accum
  
imports: import numpy
  from tensorflow.python.eager import context
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import indexed_slices
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import embedding_ops
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import resource_variable_ops
  from tensorflow.python.ops import variables
  from tensorflow.python.platform import test
  from tensorflow.python.training import momentum
label_desc: Use image node_id 1 for calling the MomentumOptimizerTest obj's underlying member method code with example usage: obj._update_nesterov_momentum_numpy(var, accum, g, lr, momentum) and returns: var,  accum