docstr: Returns (mean_ref, v_ref, weight_ref)
docstr_tok: ["Returns","(","mean_ref",",","v_ref",",","weight_ref",")"]
code: def ref_impl(
      m,
      v,
      weight,
      grad_rescale,
      beta1,
      beta2,
      lr,
      eta,
      wd,
      epsilon,
      clip_grad=-1,
  ):
      """Returns (mean_ref, v_ref, weight_ref)"""
      raise NotImplementedError()
  
file_path: mxnet/tests/python/unittest/test_contrib_optimizer.py
imports: import itertools
  import numpy
  import mxnet
  from mxnet.test_utils import *
  import pytest
  from common import xfail_when_nonstandard_decimal_separator
label_desc: Use image node_id 1 for calling the _AdamLikeTestHelper obj's underlying member method code with example usage: obj.ref_impl(m, v, weight, grad_rescale, beta1, beta2, lr, eta, wd, epsilon, clip_grad) without return types