code: def setUp(self):
      self.x = numpy.random.uniform(-1, 1, self.shape).astype(
          self.dtype
      )
  
file_path: chainerrl/tests/functions_tests/test_invert_gradients.py
imports: import unittest
  import chainer
  from chainer import cuda
  from chainer import functions
  from chainer import testing
  from chainer.testing import attr
  from chainer.testing import condition
  import numpy
  from chainerrl.functions.invert_gradients import invert_gradients
label_desc: Use image node_id 1 for calling the TestInvertGradients obj's underlying member method code with example usage: obj.setUp() without return types