tests run, ready for review

Author: Yuchen Xu

acceleration/automatic_mixed_precision.ipynb

@@ -71,7 +71,7 @@
     "import torch\n",
     "from monai.apps import download_and_extract\n",
     "from monai.config import print_config\n",
-    "from monai.data import DataLoader, CacheDataset, list_data_collate, decollate_batch\n",
+    "from monai.data import CacheDataset, DataLoader, decollate_batch\n",
     "from monai.inferers import sliding_window_inference\n",
     "from monai.losses import DiceLoss\n",
     "from monai.metrics import DiceMetric\n",