message: as_numpy_dtype is a property, not a method.
  This makes explicit that as_numpy_dtype(0) returns a scalar value, not a dtype.
diff: @@ -121,14 +121,14 @@ class AdadeltaOptimizerTest(test.TestCase):
  # TODO(lxuechen): This is hard to test in eager mode
  for slot_idx in range(2):
  self.assertAllCloseAccordingToType(
  - np.array([accum, accum], dtype=dtype.as_numpy_dtype()),
  + np.array([accum, accum], dtype=dtype.as_numpy_dtype(0)),
  self.evaluate(slot[slot_idx]),
  rtol=1e-5)
  self.assertAllCloseAccordingToType(
  np.array(
  [accum_update, accum_update],
  - dtype=dtype.as_numpy_dtype()),
  + dtype=dtype.as_numpy_dtype(0)),
  self.evaluate(slot_update[slot_idx]),
  rtol=1e-5)
  @@ -136,14 +136,14 @@ class AdadeltaOptimizerTest(test.TestCase):
  self.assertAllCloseAccordingToType(
  np.array(
  [var0_init[0] - tot_update, var0_init[1] - tot_update],
  - dtype=dtype.as_numpy_dtype()),
  + dtype=dtype.as_numpy_dtype(0)),
  self.evaluate(var0),
  rtol=1e-5)
  self.assertAllCloseAccordingToType(
  np.array(
  [var1_init[0] - tot_update, var1_init[1] - tot_update],
  - dtype=dtype.as_numpy_dtype()),
  + dtype=dtype.as_numpy_dtype(0)),
  self.evaluate(var1),
  rtol=1e-5)
  