docstr: Test profiling Engine objects works if Ignite is present.
docstr_tok: ["Test","profiling","Engine","objects","works","if","Ignite","is","present","."]
code: def test_handler(self):
      """Test profiling Engine objects works if Ignite is present."""
      from ignite.engine import Events
  
      from monai.engines import SupervisedTrainer
  
      net = torch.nn.Conv2d(1, 1, 3, padding=1)
      im = torch.rand(1, 1, 16, 16)
  
      with WorkflowProfiler(None) as wp:
          trainer = SupervisedTrainer(
              device=torch.device("cpu"),
              max_epochs=2,
              train_data_loader=[
                  {CommonKeys.IMAGE: im, CommonKeys.LABEL: im}
              ]
              * 3,
              epoch_length=3,
              network=net,
              optimizer=torch.optim.Adam(net.parameters()),
              loss_function=torch.nn.L1Loss(),
          )
  
          _ = ProfileHandler(
              "Epoch", wp, Events.EPOCH_STARTED, Events.EPOCH_COMPLETED
          ).attach(trainer)
  
          trainer.run()
  
      results = wp.get_results()
  
      self.assertSequenceEqual(set(results), {"Epoch"})
      self.assertEqual(len(results["Epoch"]), 2)
  
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 11 for calling the TestWorkflowProfiler obj's underlying member method code with example usage: obj.test_handler() without return types