code: def test_attribute_presence(self):
      self.assertEqual(self.learn_W, hasattr(self.link, "W"))
      self.assertEqual(self.bias_term, hasattr(self.link, "bias"))
  
imports: import unittest
  import numpy
  import chainer
  from chainer.backends import cuda
  from chainer import gradient_check
  from chainer import links
  from chainer import testing
  from chainer.testing import attr
  from chainer.testing import condition
label_desc: Use image node_id 2 for calling the TestScale obj's underlying member method code with example usage: obj.test_attribute_presence() without return types