class_docstr: Tests for Importer and derived classes.
code: def test_sys_importer_roundtrip(self):
      import package_a
      import package_a.subpackage
  
      importer = sys_importer
      type_ = package_a.subpackage.PackageASubpackageObject
      module_name, type_name = importer.get_name(type_)
  
      module = importer.import_module(module_name)
      self.assertIs(getattr(module, type_name), type_)
  
file_path: pytorch/test/package/test_importer.py
imports: from io import BytesIO
  import torch
  from torch.package import Importer, OrderedImporter, PackageExporter, PackageImporter, sys_importer
  from torch.testing._internal.common_utils import run_tests
label_desc: Use image node_id 2 for calling the TestImporter obj's underlying member method code with example usage: obj.test_sys_importer_roundtrip() without return types