Repository: huggingface/transformers
Pull request: Fix the deprecation warning of _torch_pytree._register_pytree_node

# What does this PR do?
Fix a deprecation warning triggered by latest PyTorch:
```
UserWarning: torch.utils._pytree._register_pytree_node is deprecated. Please use torch.utils._pytree.register_pytree_node instead.
```
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Changed files:
filename: src/transformers/utils/generic.py
patch: @@ -306,7 +306,7 @@ def __init_subclass__(cls) -> None:
         `static_graph=True` with modules that output `ModelOutput` subclasses.
         """
         if is_torch_available():
-            _torch_pytree._register_pytree_node(
+            torch_pytree_register_pytree_node(
                 cls,
                 _model_output_flatten,
                 _model_output_unflatten,
@@ -438,7 +438,11 @@ def _model_output_unflatten(values: Iterable[Any], context: "_torch_pytree.Conte
         output_type, keys = context
         return output_type(**dict(zip(keys, values)))
 
-    _torch_pytree._register_pytree_node(
+    if hasattr(_torch_pytree, "register_pytree_node"):
+        torch_pytree_register_pytree_node = _torch_pytree.register_pytree_node
+    else:
+        torch_pytree_register_pytree_node = _torch_pytree._register_pytree_node
+    torch_pytree_register_pytree_node(
         ModelOutput,
         _model_output_flatten,
         _model_output_unflatten,