code: def test_concurrent_tune_fashion_mnist_gpu(ray_start_4_cpus_2_gpus):
      torch_fashion_mnist(num_workers=1, use_gpu=True, num_samples=2)
  
imports: import os
  from tempfile import TemporaryDirectory
  import pytest
  import torch
  from ray import train
  from ray.air.constants import TRAINING_ITERATION
  from ray.train import Checkpoint, ScalingConfig
  from ray.train.examples.horovod.horovod_example import train_func
  from ray.train.examples.pytorch.torch_fashion_mnist_example import train_func_per_worker
  from ray.train.examples.tf.tensorflow_mnist_example import train_func
  from ray.train.horovod.horovod_trainer import HorovodTrainer
  from ray.train.tensorflow.tensorflow_trainer import TensorflowTrainer
  from ray.train.tests.test_tune import torch_fashion_mnist, tune_tensorflow_mnist
  from ray.train.torch.torch_trainer import TorchTrainer
label_desc: Use image node_id 6 for calling a global function with example usage: test_concurrent_tune_fashion_mnist_gpu(ray_start_4_cpus_2_gpus) without return types