message: Update tf.stack description.
diff: @@ -1194,19 +1194,24 @@ def stack(values, axis=0, name="stack"):
  For example:
  - ```python
  - x = tf.constant([1, 4])
  - y = tf.constant([2, 5])
  - z = tf.constant([3, 6])
  - tf.stack([x, y, z]) # [[1, 4], [2, 5], [3, 6]] (Pack along first dim.)
  - tf.stack([x, y, z], axis=1) # [[1, 2, 3], [4, 5, 6]]
  - ```
  + >>> x = tf.constant([1, 4])
  + >>> y = tf.constant([2, 5])
  + >>> z = tf.constant([3, 6])
  + >>> tf.stack([x, y, z])
  + <tf.Tensor: id=19, shape=(3, 2), dtype=int32, numpy=
  + array([[1, 4],
  + [2, 5],
  + [3, 6]], dtype=int32)>
  - This is the opposite of unstack. The numpy equivalent is
  + >> tf.stack([x, y, z], axis=1)
  + <tf.Tensor: id=24, shape=(2, 3), dtype=int32, numpy=
  + array([[1, 2, 3],
  + [4, 5, 6]], dtype=int32)>
  - ```python
  - tf.stack([x, y, z]) = np.stack([x, y, z])
  - ```
  + This is the opposite of unstack. The numpy equivalent is `np.stack`
  +
  + >>> np.array_equal(np.stack([x, y, z]), tf.stack([x, y, z]))
  + True
  Args:
  values: A list of `Tensor` objects with the same shape and type.
  