code: def test_swa_auto_mode_detection(self):
      # Tests that SWA mode (auto or manual) is chosen correctly based on
      # parameters provided
  
      # Auto mode
      x, y, loss_fun, base_opt = self._define_vars_loss_opt()
      swa_start = 5
      swa_freq = 2
      swa_lr = 0.001
  
      opt = StochasticWeightAveraging(
          base_opt,
          swa_start=swa_start,
          swa_freq=swa_freq,
          swa_lr=swa_lr,
      )
      assert equal(opt._auto_mode, True)
  
      opt = StochasticWeightAveraging(
          base_opt, swa_start=swa_start, swa_freq=swa_freq
      )
      assert equal(opt._auto_mode, True)
  
      with self.assertWarnsRegex("Some of swa_start, swa_freq is None"):
          opt = StochasticWeightAveraging(
              base_opt, swa_start=swa_start, swa_lr=swa_lr
          )
          assert equal(opt._auto_mode, False)
  
      with self.assertWarnsRegex("Some of swa_start, swa_freq is None"):
          opt = StochasticWeightAveraging(
              base_opt, swa_freq=swa_freq, swa_lr=swa_lr
          )
          assert equal(opt._auto_mode, False)
  
      with self.assertWarnsRegex("Some of swa_start, swa_freq is None"):
          opt = StochasticWeightAveraging(base_opt, swa_start=swa_start)
          assert equal(opt._auto_mode, False)
  
      with self.assertWarnsRegex("Some of swa_start, swa_freq is None"):
          opt = StochasticWeightAveraging(base_opt, swa_freq=swa_freq)
          assert equal(opt._auto_mode, False)
  
      with self.assertWarnsRegex("Some of swa_start, swa_freq is None"):
          opt = StochasticWeightAveraging(base_opt, swa_lr=swa_lr)
          assert equal(opt._auto_mode, False)
  
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 15 for calling the TestSWA obj's underlying member method code with example usage: obj.test_swa_auto_mode_detection() without return types