code: def test_create_variations_gpu(self):
      device = "cuda" if torch.cuda.is_available() else "cpu"
      if device == "cuda":
          for model_name in self.resnet_variants:
              resnet = ResNetGenerator(model_name)
              model = BYOL(get_backbone(resnet)).to(device)
              self.assertIsNotNone(model)
      else:
          pass
  
file_path: lightly/tests/models/test_ModelsBYOL.py
imports: import unittest
  import torch
  import torch.nn
  import torchvision
  import lightly
  from lightly.models import BYOL, ResNetGenerator
label_desc: Use image node_id 3 for calling the TestModelsBYOL obj's underlying member method code with example usage: obj.test_create_variations_gpu() without return types