code: def testGradNonArrayOutput(self):
      def f(_):
          return 1.0
  
      g = extensions.grad(f)
      with self.assertRaisesWithPredicateMatch(
          ValueError, r"result .* must be an ndarray"
      ):
          g(tf_np.asarray(1.0))
  
imports: import functools
  import itertools
  from absl import flags
  from absl.testing import parameterized
  from jax import lax
  import numpy
  import tensorflow.compat.v2
  from trax.tf_numpy import extensions
  import trax.tf_numpy.numpy
label_desc: Use image node_id 7 for calling the ExtensionsTest obj's underlying member method code with example usage: obj.testGradNonArrayOutput() and returns: int