diff --git a/library/device_utils.py b/library/device_utils.py
index 93371ca6..546fb386 100644
--- a/library/device_utils.py
+++ b/library/device_utils.py
@@ -15,6 +15,7 @@ except Exception:
 
 try:
     import intel_extension_for_pytorch as ipex  # noqa
+
     HAS_XPU = torch.xpu.is_available()
 except Exception:
     HAS_XPU = False
@@ -32,6 +33,9 @@ def clean_memory():
 
 @functools.lru_cache(maxsize=None)
 def get_preferred_device() -> torch.device:
+    r"""
+    Do not call this function from training scripts. Use accelerator.device instead.
+    """
     if HAS_CUDA:
         device = torch.device("cuda")
     elif HAS_XPU:
@@ -43,6 +47,7 @@ def get_preferred_device() -> torch.device:
     print(f"get_preferred_device() -> {device}")
     return device
 
+
 def init_ipex():
     """
     Apply IPEX to CUDA hijacks using `library.ipex.ipex_init`.
@@ -54,10 +59,11 @@ def init_ipex():
     try:
         if HAS_XPU:
             from library.ipex import ipex_init
+
             is_initialized, error_message = ipex_init()
             if not is_initialized:
                 print("failed to initialize ipex:", error_message)
         else:
             return
     except Exception as e:
-        print("failed to initialize ipex:", e)
\ No newline at end of file
+        print("failed to initialize ipex:", e)