code: def test_with_optimizer(self):
      optimizer = mock.Mock()
      optimizer.x = 0
      extension = extensions.StepShift(
          "x", self.gamma, self.step, self.init, self.target, optimizer
      )
      self._run_trainer(extension, self.expect, optimizer)
  
file_path: chainer/tests/chainer_tests/training_tests/extensions_tests/test_step_shift.py
imports: import unittest
  import mock
  from chainer import testing
  from chainer import training
  from chainer.training import extensions
label_desc: Use image node_id 5 for calling the TestStepShift obj's underlying member method code with example usage: obj.test_with_optimizer() without return types