code: def test_dynamic_neighbor_allreduce_optimizer(
      device, atc_style, kwargs
  ):
      error_threshold = kwargs.get("error_threshold", 1.5)
  
      (
          problem_builder,
          train_dataloader,
          test_dataloader,
          model,
          optimizer,
          num_epochs,
      ) = problem_setup()
  
      isCUDA = pin_model_to_device(device, model)
  
      base_dist_optimizer = (
          bf.DistributedAdaptThenCombineOptimizer
          if atc_style
          else bf.DistributedAdaptWithCombineOptimizer
      )
      optimizer = base_dist_optimizer(
          optimizer,
          model=model,
          communication_type=bf.CommunicationType.neighbor_allreduce,
      )
  
      dynamic_topo_gen = topology_util.GetDynamicOnePeerSendRecvRanks(
          bf.load_topology(), bf.rank()
      )
  
      # Train and test
      train_mse = []
      test_mse = []
      for _ in range(num_epochs):
          dynamic_neighbor_allreduce_train(
              model,
              optimizer,
              train_dataloader,
              isCUDA,
              dynamic_topo_gen,
          )
          train_mse.append(evaluation(model, train_dataloader, isCUDA))
          test_mse.append(evaluation(model, test_dataloader, isCUDA))
      train_mse = np.array(train_mse)
      test_mse = np.array(test_mse)
  
      # Check if the MSEs in the last three epochs are small enough
      assert (
          train_mse[-3:].max()
          < error_threshold * problem_builder.noise_level**2
      ), "Train MSE in the last three epochs doesn't coverge."
      assert (
          test_mse[-3:].max()
          < error_threshold * problem_builder.noise_level**2
      ), "Train MSE in the last three epochs doesn't coverge."
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import pytest
  import numpy
  import torch
  import torch.nn
  import torch.optim
  from torch.utils.data import Dataset, DataLoader
  import bluefog.torch
  from bluefog.common import topology_util
label_desc: Use image node_id 10 for calling a global function with example usage: test_dynamic_neighbor_allreduce_optimizer(device, atc_style, kwargs) without return types