code: def before_test(self, test_name):
      if self.use_weights and isinstance(self.axis, tuple):
          # This condition is not supported
          raise unittest.SkipTest(
              "Tuple axis is not supported when weights is given"
          )
  
imports: import unittest
  import numpy
  import six
  from chainer import functions
  from chainer import testing
  from chainer.testing import attr
  from chainer import utils
label_desc: Use image node_id 2 for calling the TestAverage obj's underlying member method code with example usage: obj.before_test(test_name) without return types