OptionalImportError when using pytorch 2.7

22:12:13  ======================================================================
22:12:13  ERROR: test_milmodel (unittest.loader._FailedTest)
22:12:13  ----------------------------------------------------------------------
22:12:13  ImportError: Failed to import test module: test_milmodel
22:12:13  Traceback (most recent call last):
22:12:13    File "/usr/lib/python3.10/unittest/loader.py", line 154, in loadTestsFromName
22:12:13      module = __import__(module_name)
22:12:13    File "/tmp/tmp.tAhlxKhK20/tests/networks/nets/test_milmodel.py", line 53, in <module>
22:12:13      backbone = models.densenet121(pretrained=False)
22:12:13    File "/usr/local/lib/python3.10/dist-packages/monai/utils/module.py", line 420, in __getattr__
22:12:13      raise self._exception
22:12:13    File "/usr/local/lib/python3.10/dist-packages/monai/utils/module.py", line 378, in optional_import
22:12:13      pkg = __import__(module)  # top level module
22:12:13    File "/usr/local/lib/python3.10/dist-packages/torchvision/__init__.py", line 10, in <module>
22:12:13      from torchvision import _meta_registrations, datasets, io, models, ops, transforms, utils  # usort:skip
22:12:13    File "/usr/local/lib/python3.10/dist-packages/torchvision/_meta_registrations.py", line 26, in <module>
22:12:13      def meta_roi_align(input, rois, spatial_scale, pooled_height, pooled_width, sampling_ratio, aligned):
22:12:13    File "/usr/local/lib/python3.10/dist-packages/torchvision/_meta_registrations.py", line 18, in wrapper
22:12:13      if torchvision.extension._has_ops():
22:12:13  monai.utils.module.OptionalImportError: import torchvision.models (partially initialized module 'torchvision' has no attribute 'extension' (most likely due to a circular import)).
22:12:13  
22:12:13  For details about installing the optional dependencies, please visit:
22:12:13      https://docs.monai.io/en/latest/installation.html#installing-the-recommended-dependencies

Start by reproducing the failure from tests/networks/nets/test_milmodel.py, especially the models.densenet121(pretrained=False) import, with the reported PyTorch 2.7 environment. Inspect the OptionalImportError traceback through monai/utils/module.py and verify the test module imports successfully with the relevant optional dependencies installed.