code: def test_early_stop_val_metric(self):
      def _train_func(engine, batch):
          pass
  
      trainer = Engine(_train_func)
      validator = Engine(_train_func)
      validator.state.metrics["val_acc"] = 0.90
  
      @trainer.on(Events.EPOCH_COMPLETED)
      def run_validation(engine):
          validator.state.metrics["val_acc"] += 0.01
          validator.run(range(3))
  
      handler = EarlyStopHandler(
          patience=3,
          score_function=lambda x: x.state.metrics["val_acc"],
          trainer=None,
          min_delta=0.1,
          cumulative_delta=True,
          epoch_level=True,
      )
      handler.attach(validator)
      handler.set_trainer(trainer=trainer)
  
      trainer.run(range(3), max_epochs=5)
      self.assertEqual(trainer.state.iteration, 12)
      self.assertEqual(trainer.state.epoch, 4)
  
file_path: MONAI/tests/test_handler_early_stop.py
imports: from __future__ import annotations
  import unittest
  from ignite.engine import Engine, Events
  from monai.handlers import EarlyStopHandler
label_desc: Use image node_id 2 for calling the TestHandlerEarlyStop obj's underlying member method code with example usage: obj.test_early_stop_val_metric() without return types