message: Fix doctest for ensure_shape
diff: @@ -2126,6 +2126,10 @@ def ensure_shape(x, shape, name=None):
  ... return tf.ensure_shape(tensor, [3, 3])
  >>>
  >>> f(tf.zeros([3, 3])) # Passes
  + <tf.Tensor: shape=(3, 3), dtype=float32, numpy=
  + array([[0., 0., 0.],
  + [0., 0., 0.],
  + [0., 0., 0.]], dtype=float32)>
  >>> f([1, 2, 3]) # fails
  Traceback (most recent call last):
  ...
  