code: def setUp(self):
      self.decay = 0.9
      self.size = 3
      self.link = links.BatchRenormalization(
          self.size, decay=self.decay, eps=self.eps
      )
      self.x = numpy.random.uniform(-1, 1, (self.nx, self.size)).astype(
          numpy.float32
      )
      self.y = numpy.random.uniform(-1, 1, (self.ny, self.size)).astype(
          numpy.float32
      )
  
imports: import unittest
  import numpy
  import six
  import chainer
  from chainer.backends import cuda
  from chainer import links
  from chainer import testing
  from chainer.testing import attr
label_desc: Use image node_id 1 for calling the TestPopulationStatistics obj's underlying member method code with example usage: obj.setUp() without return types