code: def testEmptyFails(self):
      @custom_gradient.custom_gradient
      def id_bad_grad(x):
          y = array_ops.identity(x)
  
          def grad_fn(dy):
              # dx = constant_op.constant(np.zeros((1, 4)), dtype=dtypes.float32)
              dx = array_ops.transpose(dy)
              return dx
  
          return y, grad_fn
  
      def f(x):
          return id_bad_grad(x)
  
      x = constant_op.constant(
          np.random.random_sample((0, 3)), dtype=dtypes.float32
      )
      bad = r"Empty gradient has wrong shape: expected \(0, 3\), got \(3, 0\)"
      with self.assertRaisesRegex(ValueError, bad):
          gradient_checker.compute_gradient(f, [x])
  
imports: import numpy
  from tensorflow.python.eager import backprop
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import sparse_tensor
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import custom_gradient
  from tensorflow.python.ops import gradient_checker_v2
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import nn_ops
  from tensorflow.python.ops import sparse_ops
  import tensorflow.python.ops.nn_grad
  from tensorflow.python.platform import test
  from tensorflow.python.platform import tf_logging
label_desc: Use image node_id 13 for calling the GradientCheckerTest obj's underlying member method code with example usage: obj.testEmptyFails() and returns: y,  grad_fn, id_bad_grad, dx