Fix eager note

Author: lamberta

samples/core/guide/autograph.ipynb

@@ -198,7 +198,7 @@
       },
       "cell_type": "markdown",
       "source": [
-        "Note: AutoGraph converted code runs in eager execution as an eager-Python function. To run in-graph, use explicit graphs (as this notebook uses) or use `tf.contrib.eager.defun`."
+        "Note: AutoGraph converted code is designed to run during graph execution. When eager exectuon is enabled, use explicit graphs (as this example shows) or `tf.contrib.eager.defun`."
       ]
     },
     {