new_contents: import unittest
  
  import chainer
  import numpy
  
  from chainer import testing
  from chainer import training
  from chainer.training import triggers
  from chainer.training import util
  
  
  class DummyUpdater(training.Updater):
  
      def __init__(self):
          self.iteration = 0
  
      def finalize(self):
          pass
  
      def get_all_optimizers(self):
          return {}
  
      def update(self):
          self.iteration += 1
  
      @property
      def epoch(self):
          return 1
  
      @property
      def is_new_epoch(self):
          return False
  
  
  def _test_trigger(self, trigger, key, accuracies, expected):
      updater = DummyUpdater()
      trainer = training.Trainer(updater)
      for accuracy, expected in zip(accuracies, expected):
          updater.update()
          trainer.observation = {key: accuracy}
          self.assertEqual(trigger(trainer), expected)
  
  
  class TestEarlyStoppingTrigger(unittest.TestCase):
  
      def test_early_stopping_trigger(self):
          key = 'main/accuracy'
          trigger = triggers.EarlyStoppingTrigger(monitor=key, patients=3,
                                                  trigger=(1, 'iteration'),
                                                  verbose=False)
          trigger = util.get_trigger(trigger)
  
          accuracies = [0.5, 0.5, 0.6, 0.7, 0.6, 0.4, 0.3, 0.2]
          accuracies = numpy.asarray([
              chainer.Variable(numpy.asarray(acc, dtype=numpy.float32))
              for acc in accuracies])
  
          expected = [False, False, False, False, False, False, False, True]
          _test_trigger(self, trigger, key, accuracies, expected)
  
  
  testing.run_module(__name__, __file__)
  
subject: Add test for early stopping trigger