code: def setUpBase(self):
      self.l1 = ConstantStubLink(np.random.uniform(size=(1, 3, 24, 24)))
      self.f1 = DummyFunc()
      self.f2 = DummyFunc()
      self.l2 = ConstantStubLink(np.random.uniform(size=(1, 3, 24, 24)))
  
      self.link = PickableSequentialChain()
      with self.link.init_scope():
          self.link.l1 = self.l1
          self.link.f1 = self.f1
          self.link.f2 = self.f2
          self.link.l2 = self.l2
  
      if self.pick:
          self.link.pick = self.pick
  
      self.x = np.random.uniform(size=(1, 3, 24, 24))
  
      if not hasattr(self, "assertRaisesRegex"):
          self.assertRaisesRegex = self.assertRaisesRegexp
  
imports: import numpy
  import unittest
  import chainer
  from chainer.backends.cuda import to_cpu
  from chainer.function import Function
  from chainer import testing
  from chainer.testing import attr
  from chainercv.links import PickableSequentialChain
  from chainercv.utils.testing import ConstantStubLink
label_desc: Use image node_id 1 for calling the PickableSequentialChainTestBase obj's underlying member method code with example usage: obj.setUpBase() without return types