code: def testEmptyGradient(self):
      for data_format, use_gpu in ("NHWC", False), ("NHWC", True):
          for shape in (0, 0), (2, 0), (0, 2):
              self._testGradient(
                  np.random.randn(*shape),
                  np.random.randn(shape[-1]),
                  dtypes.float64,
                  data_format,
                  use_gpu,
              )
  
      for data_format, use_gpu in [
          ("NHWC", False),
          ("NHWC", True),
          ("NCHW", False),
          ("NCHW", True),
      ]:
          for shape in (4, 3, 0), (4, 0, 3), (0, 4, 3):
              self._testGradient(
                  np.random.randn(*shape),
                  np.random.randn(shape[-1]),
                  dtypes.float64,
                  data_format,
                  use_gpu,
              )
  
imports: import numpy
  from tensorflow.python.eager import backprop
  from tensorflow.python.eager import context
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import errors_impl
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import gradient_checker
  from tensorflow.python.ops import gradient_checker_v2
  from tensorflow.python.ops import gradients_impl
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import nn_ops
  import tensorflow.python.ops.nn_grad
  from tensorflow.python.platform import test
label_desc: Use image node_id 26 for calling the BiasAddTestBase obj's underlying member method code with example usage: obj.testEmptyGradient() without return types