code: def test_without_init(self):
      self.optimizer.x = self.init
      extension = extensions.PolynomialShift(
          "x", self.rate, self.max_count, target=self.target
      )
      self._run_trainer(extension, self.expect)
  
file_path: chainer/tests/chainer_tests/training_tests/extensions_tests/test_polynomial_shift.py
imports: import unittest
  import mock
  from chainer import testing
  from chainer.training import extensions
  from chainer.training import util
label_desc: Use image node_id 4 for calling the TestPolynomialShift obj's underlying member method code with example usage: obj.test_without_init() without return types