code: def test_bernoulli_nll_gpu(self):
      self.check_bernoulli_nll(cuda.to_gpu(self.x), cuda.to_gpu(self.y))
  
imports: import unittest
  import numpy
  import chainer
  from chainer.backends import cuda
  from chainer import functions
  from chainer import testing
  from chainer.testing import attr
  from chainer.testing import condition
label_desc: Use image node_id 4 for calling the TestBernoulliNLL obj's underlying member method code with example usage: obj.test_bernoulli_nll_gpu() without return types