message: Fix formatting error in tf.stack.
diff: @@ -1297,7 +1297,7 @@ def stack(values, axis=0, name="stack"):
  [2, 5],
  [3, 6]], dtype=int32)>
  - >> tf.stack([x, y, z], axis=1)
  + >>> tf.stack([x, y, z], axis=1)
  <tf.Tensor: shape=(2, 3), dtype=int32, numpy=
  array([[1, 2, 3],
  [4, 5, 6]], dtype=int32)>
  