diff --git a/12_custom_models_and_training_with_tensorflow.ipynb b/12_custom_models_and_training_with_tensorflow.ipynb
index add425f..bc0fde2 100644
--- a/12_custom_models_and_training_with_tensorflow.ipynb
+++ b/12_custom_models_and_training_with_tensorflow.ipynb
@@ -1859,21 +1859,6 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "from sklearn.datasets import fetch_california_housing\n",
-    "from sklearn.model_selection import train_test_split\n",
-    "from sklearn.preprocessing import StandardScaler\n",
-    "\n",
-    "housing = fetch_california_housing()\n",
-    "X_train_full, X_test, y_train_full, y_test = train_test_split(\n",
-    "    housing.data, housing.target.reshape(-1, 1), random_state=42)\n",
-    "X_train, X_valid, y_train, y_valid = train_test_split(\n",
-    "    X_train_full, y_train_full, random_state=42)\n",
-    "\n",
-    "scaler = StandardScaler()\n",
-    "X_train_scaled = scaler.fit_transform(X_train)\n",
-    "X_valid_scaled = scaler.transform(X_valid)\n",
-    "X_test_scaled = scaler.transform(X_test)\n",
-    "\n",
     "class MyMultiLayer(keras.layers.Layer):\n",
     "    def call(self, X):\n",
     "        X1, X2 = X\n",