docstr: Test that the profiler correctly produces an empty result when nothing happens in a context.
docstr_tok: ["Test","that","the","profiler","correctly","produces","an","empty","result","when","nothing","happens","in","a","context","."]
code: def test_empty(self):
      """Test that the profiler correctly produces an empty result when nothing happens in a context."""
      wp = WorkflowProfiler()
  
      with wp:
          pass
  
      self.assertEqual(wp.get_results(), {})
  
imports: from __future__ import annotations
  import datetime
  import os
  import unittest
  from io import StringIO
  import torch
  import monai.transforms
  from monai.data import Dataset, ThreadDataLoader
  from monai.utils import first, optional_import
  from monai.utils.enums import CommonKeys
  from monai.utils.profiling import ProfileHandler, ProfileResult, WorkflowProfiler
  from tests.utils import SkipIfNoModule
label_desc: Use image node_id 2 for calling the TestWorkflowProfiler obj's underlying member method code with example usage: obj.test_empty() without return types