code: def _test_basic_cases(self, constructor, ignore_multidevice=False):
      # non-contiguous parameters
      self._test_basic_cases_template(
          torch.randn(10, 5, 2)[..., 0],
          torch.randn(10, 2)[..., 0],
          torch.randn(5),
          constructor,
      )
      # CUDA
      if not torch.cuda.is_available():
          return
      self._test_basic_cases_template(
          torch.randn(10, 5).cuda(),
          torch.randn(10).cuda(),
          torch.randn(5).cuda(),
          constructor,
      )
      # Multi-GPU
      if not torch.cuda.device_count() > 1 or ignore_multidevice:
          return
      self._test_basic_cases_template(
          torch.randn(10, 5).cuda(0),
          torch.randn(10).cuda(1),
          torch.randn(5).cuda(0),
          constructor,
      )
  
imports: import contextlib
  import functools
  import re
  import warnings
  from unittest import TestCase
  import torch
  from pytext.optimizer import Lamb, StochasticWeightAveraging
  from torch import nn, optim, sparse
  from torch.autograd import Variable
  from torch.utils import data
label_desc: Use image node_id 5 for calling the TestSWA obj's underlying member method code with example usage: obj._test_basic_cases(constructor, ignore_multidevice) without return types