code: def setUp(self):
      self.target = SimpleLink(
          np.arange(6, dtype=np.float32).reshape((2, 3)),
          np.arange(3, -3, -1, dtype=np.float32).reshape((2, 3)),
      )
  
file_path: chainercv/tests/links_tests/model_tests/ssd_tests/test_gradient_scaling.py
imports: import numpy
  import unittest
  import chainer
  from chainer import optimizers
  from chainer import testing
  from chainer.testing import attr
  from chainercv.links.model.ssd import GradientScaling
label_desc: Use image node_id 1 for calling the TestGradientScaling obj's underlying member method code with example usage: obj.setUp() without return types