class_docstr: Tests correctness of the Y = scale @ x transformation.
class_docstr_tok: ["Tests","correctness","of","the","Y","=","scale","@","x","transformation","."]
code: def testNonVariableGradients(self):
      def _func(scale):
          b = scale_lib.Scale(scale=scale)
          return b.forward(0.1)
  
      value, grad = gradient.value_and_gradient(_func, [2.0])
      self.assertAllNotNone([value, grad])
      self.assertAllAssertsNested(self.assertNotAllZero, grad)
  
imports: from absl.testing import parameterized
  import numpy
  import tensorflow.compat.v2
  from tensorflow_probability.python.bijectors import bijector_test_util
  from tensorflow_probability.python.bijectors import scale
  from tensorflow_probability.python.internal import test_util
  from tensorflow_probability.python.math import gradient
label_desc: Use image node_id 8 for calling the ScaleBijectorTest obj's underlying member method code with example usage: obj.testNonVariableGradients() and returns: b