code: def _test_trigger(self, trigger, key, accuracies, expected):
      trainer = testing.training.get_trainer_with_mock_updater(
          stop_trigger=None, iter_per_epoch=1
      )
  
      for accuracy, expected in zip(accuracies, expected):
          trainer.updater.update()
          trainer.observation = {key: accuracy}
          self.assertEqual(trigger(trainer), expected)
  
file_path: chainer/tests/chainer_tests/training_tests/triggers_tests/test_early_stopping_trigger.py
imports: import unittest
  import numpy
  import pytest
  import chainer
  from chainer import testing
  from chainer.training import triggers
  from chainer.training import util
label_desc: Use image node_id 1 for calling a global function with example usage: _test_trigger(trigger, key, accuracies, expected) without return types