code: def generate_inputs(self):
      x = numpy.random.uniform(-1, 1, self.shape).astype(self.dtype)
      y = numpy.random.uniform(-1, 1, self.shape).astype(self.dtype)
      return x, y
  
file_path: chainer/tests/chainer_tests/functions_tests/normalization_tests/test_group_normalization.py
imports: import numpy
  import six
  from chainer import functions
  import chainer.functions.normalization.group_normalization
  from chainer import testing
label_desc: Use image node_id 1 for calling the TestMulInvStd obj's underlying member method code with example usage: obj.generate_inputs() and returns: x,  y