fix forecast/backtest variables

Author: benman1

chapter7/Silverkite.ipynb

@@ -157,8 +157,8 @@
    },
    "outputs": [],
    "source": [
-    "ts = result.forecast\n",
-    "ts.plot().show(renderer=\"colab\")  # leave out the renderer argument if you are not on google colab!"
+    "forecast = result.forecast\n",
+    "forecast.plot().show(renderer=\"colab\")  # leave out the renderer argument if you are not on google colab!"
    ]
   },
   {
@@ -192,6 +192,7 @@
    "source": [
     "from collections import defaultdict\n",
     "\n",
+    "backtest = result.backtest\n",
     "backtest_eval = defaultdict(list)\n",
     "for metric, value in backtest.train_evaluation.items():\n",
     "    backtest_eval[metric].append(value)\n",