code: def _update_momentum(p, g, v, lr, momentum, wd, init_lr):
      eta_t = lr / init_lr
      v[...] = v * momentum + lr * g
      p[...] = p - v - eta_t * wd * p
  
file_path: nnabla/python/test/solver/test_sgdw.py
imports: import pytest
  import nnabla.solvers
  import numpy
  from solver_test_utils import solver_tester, RefSolver, MixinWeightDecayFused
  from nbla_test_utils import list_context
label_desc: Use image node_id 1 for calling a global function with example usage: _update_momentum(p, g, v, lr, momentum, wd, init_lr) without return types