code: def test_mark_strict_with_container_type(self):
      @_mark_strict_experimental
      class B(torch.nn.Module):
          def __init__(self):
              super().__init__()
  
          def forward(self, x):
              x0 = x[0][0]
              return x0.sum()
  
      class M(torch.nn.Module):
          def __init__(self):
              super().__init__()
              self.submodule = B()
  
          def forward(self, x):
              return self.submodule(x)
  
      inp = ((torch.randn(3),),)
      with self.assertRaisesRegex(
          RuntimeError, "strict_mode HOO doesn't work unless"
      ):
          ep = torch.export.export(M(), inp, strict=False)
  
file_path: pytorch/test/export/test_experimental.py
imports: import unittest
  import torch
  import torch._dynamo
  from torch._dynamo.test_case import run_tests, TestCase
  from torch._export.wrappers import _mark_strict_experimental
  from torch._functorch.aot_autograd import aot_export_module
  from torch.testing import FileCheck
label_desc: Use image node_id 2 for calling the TestExperiment obj's underlying member method code with example usage: obj.test_mark_strict_with_container_type() and returns: x0, self