code: def _decorrelated_batch_normalization(x, mean, projection, groups):
      xs = numpy.split(x, groups, axis=1)
      assert mean.shape[0] == groups
      assert projection.shape[0] == groups
      ys = [
          _decorrelated_batch_normalization_1group(xi, m, p)
          for (xi, m, p) in zip(xs, mean, projection)
      ]
      return numpy.concatenate(ys, axis=1)
  
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 1 for calling a global function with example usage: _decorrelated_batch_normalization(x, mean, projection, groups) and returns: numpy