minor fix to driver

Keras_Tensorflow/01_DevelopModelDriver.ipynb

@@ -100,8 +100,7 @@
     "        start = t.default_timer()\n",
     "\n",
     "        base64Dict = json.loads(inputString) \n",
-    "        for k, v in base64Dict.items():\n",
-    "            img_file_name, base64Img = k, v \n",
+    "        img_file_name, base64Img= next(iter(base64Dict.items()))\n",
     "        img_array = _base64img_to_numpy(base64Img)\n",
     "        preds = scoring_func(img_array)\n",
     "        responses = {img_file_name: preds}\n",