Fix review comments.

Add note about keras layers and models.

Author: MarkDaoust

samples/core/guide/autograph_control_flow.ipynb

@@ -385,7 +385,7 @@
         "with tf.Graph().as_default():  \n",
         "  with tf.Session():\n",
         "    try:\n",
-        "      print(tf_f(tf.constant(0)).eval())\n",
+        "      print(f(tf.constant(0)).eval())\n",
         "    except tf.errors.InvalidArgumentError as e:\n",
         "      print('Got error message:\\n    %s' % e.message)"
       ],
@@ -451,7 +451,8 @@
         "def f(n):\n",
         "  z = []\n",
         "  # We ask you to tell us the element dtype of the list\n",
-        "  z = autograph.utils.set_element_type(z, tf.int32)\n",
+        "  autograph.utils.set_element_type(z, tf.int32)\n",
+        "  \n",
         "  for i in range(n):\n",
         "    z.append(i)\n",
         "  # when you're done with the list, stack it\n",
@@ -474,7 +475,7 @@
       },
       "cell_type": "markdown",
       "source": [
-        "### Nested If statement"
+        "### Nested if statements"
       ]
     },
     {
@@ -571,17 +572,31 @@
       "execution_count": 0,
       "outputs": []
     },
+    {
+      "metadata": {
+        "id": "hy99pRWpMcuN",
+        "colab_type": "text"
+      },
+      "cell_type": "markdown",
+      "source": [
+        ""
+      ]
+    },
     {
       "metadata": {
         "id": "4LfnJjm0Bm0B",
         "colab_type": "text"
       },
       "cell_type": "markdown",
       "source": [
-        "## Advanced example: A training, loop in-graph\n",
+        "## Advanced example: A training loop in-graph\n",
         "\n",
         "Writing control flow in AutoGraph is easy, so running a training loop in a TensorFlow graph should be easy as well!  \n",
         "\n",
+        "<!--TODO(markdaoust) link to examples showing autograph **in** keras models when ready-->\n",
+        "\n",
+        "Important: While this example wraps up a `tf.keras.Model` using autograph, `tf.contrib.autograph` is fully compatible with `tf.keras` and can be used in the definitions [custom of keras layers and models](http://tensorflow.org/guide/keras#build_advanced_models). The easiest way is to `@autograph.convert()` the `call` method.\n",
+        "\n",
         "Here, we show an example of training a simple Keras model on MNIST, where the entire training process -- loading batches, calculating gradients, updating parameters, calculating validation accuracy, and repeating until convergence -- is done in-graph."
       ]
     },
@@ -700,20 +715,20 @@
         "  # to convert these lists into their graph equivalent,\n",
         "  # we need to specify the element type of the lists.\n",
         "  train_losses = []\n",
-        "  train_losses = autograph.utils.set_element_type(train_losses, tf.float32)\n",
+        "  autograph.utils.set_element_type(train_losses, tf.float32)\n",
         "  test_losses = []\n",
-        "  test_losses = autograph.utils.set_element_type(test_losses, tf.float32)\n",
+        "  autograph.utils.set_element_type(test_losses, tf.float32)\n",
         "  train_accuracies = []\n",
-        "  train_accuracies = autograph.utils.set_element_type(train_accuracies, tf.float32)\n",
+        "  autograph.utils.set_element_type(train_accuracies, tf.float32)\n",
         "  test_accuracies = []\n",
-        "  test_accuracies = autograph.utils.set_element_type(test_accuracies, tf.float32)\n",
+        "  autograph.utils.set_element_type(test_accuracies, tf.float32)\n",
         "  \n",
         "  # This entire training loop will be run in-graph.\n",
         "  i = tf.constant(0)\n",
         "  while i < hp.max_steps:\n",
         "    train_x, train_y = get_next_batch(train_ds)\n",
         "    test_x, test_y = get_next_batch(test_ds)\n",
-        "    # add get next\n",
+        "\n",
         "    step_train_loss, step_train_accuracy = fit(m, train_x, train_y, opt)\n",
         "    step_test_loss, step_test_accuracy = predict(m, test_x, test_y)\n",
         "    if i % (hp.max_steps // 10) == 0:\n",
@@ -790,19 +805,6 @@
       ],
       "execution_count": 0,
       "outputs": []
-    },
-    {
-      "metadata": {
-        "id": "ZpEIfs5jn6jw",
-        "colab_type": "code",
-        "colab": {}
-      },
-      "cell_type": "code",
-      "source": [
-        ""
-      ],
-      "execution_count": 0,
-      "outputs": []
     }
   ]
 }