code: def forward_expected(self, link, inputs):
      (x,) = inputs
      if self.test:
          mean = link.avg_mean
          projection = link.avg_projection
      else:
          mean = _calc_mean(x, self.groups)
          projection = _calc_projection(x, mean, link.eps, self.groups)
      y_expect = _decorrelated_batch_normalization(
          x, mean, projection, self.groups
      )
      return (y_expect,)
  
imports: import contextlib
  import os
  import tempfile
  import unittest
  import numpy
  import chainer
  from chainer import links
  from chainer import testing
label_desc: Use image node_id 5 for calling the DecorrelatedBatchNormalizationTest obj's underlying member method code with example usage: obj.forward_expected(link, inputs) and returns: y_expect