content: import os.path as osp
  import tempfile
  
  import torch.nn as nn
  from tools.pytorch2onnx import _convert_batchnorm, pytorch2onnx
  
  
  class TestModel(nn.Module):
  
      def __init__(self):
          super().__init__()
          self.conv = nn.Conv3d(1, 2, 1)
          self.bn = nn.SyncBatchNorm(2)
  
      def forward(self, x):
          return self.bn(self.conv(x))
  
      def forward_dummy(self, x):
          return (self.forward(x), )
  
  
  def test_onnx_exporting():
      with tempfile.TemporaryDirectory() as tmpdir:
          out_file = osp.join(tmpdir, 'tmp.onnx')
          model = TestModel()
          model = _convert_batchnorm(model)
          # test exporting
          pytorch2onnx(model, (1, 1, 1, 1, 1), output_file=out_file)
  