Revert notebook example to base execution engine (#3852)

examples/notebooks/Retiarii_example_multi-trial_NAS.ipynb

@@ -55,7 +55,7 @@
     "\n",
     "class Net(nn.Module):\n",
     "    def __init__(self):\n",
-    "        super(Net, self).__init__()\n",
+    "        super().__init__()\n",
     "        self.conv1 = nn.Conv2d(3, 6, 3, padding=1)\n",
     "        self.pool = nn.MaxPool2d(2, 2)\n",
     "        self.conv2 = nn.Conv2d(6, 16, 3, padding=1)\n",
@@ -109,12 +109,10 @@
    "source": [
     "import torch.nn.functional as F\n",
     "import nni.retiarii.nn.pytorch as nn\n",
-    "from nni.retiarii import model_wrapper\n",
     "\n",
-    "@model_wrapper\n",
     "class Net(nn.Module):\n",
     "    def __init__(self):\n",
-    "        super(Net, self).__init__()\n",
+    "        super().__init__()\n",
     "        # self.conv1 = nn.Conv2d(3, 6, 3, padding=1)\n",
     "        self.conv1 = nn.LayerChoice([nn.Conv2d(3, 6, 3, padding=1), nn.Conv2d(3, 6, 5, padding=2)])\n",
     "        self.pool = nn.MaxPool2d(2, 2)\n",
@@ -304,6 +302,7 @@
     "exp_config.max_trial_number = 10\n",
     "exp_config.trial_gpu_number = 2\n",
     "exp_config.max_experiment_duration = '5m'\n",
+    "exp_config.execution_engine = 'base'\n",
     "exp_config.training_service.use_active_gpu = True"
    ]
   },

examples/notebooks/tabular_data_classification_in_AML.ipynb

@@ -127,9 +127,7 @@
    "source": [
     "import nni.retiarii.nn.pytorch as nn\n",
     "import torch.nn.functional as F\n",
-    "from nni.retiarii import model_wrapper\n",
     "\n",
-    "@model_wrapper\n",
     "class Net(nn.Module):\n",
     "\n",
     "    def __init__(self, input_size):\n",
@@ -287,6 +285,7 @@
     "exp_config.trial_concurrency = 2\n",
     "exp_config.max_trial_number = 20\n",
     "exp_config.max_experiment_duration = '2h'\n",
+    "exp_config.execution_engine = 'base'\n",
     "exp_config.nni_manager_ip = '' # your nni_manager_ip"
    ]
   },