Repository: huggingface/transformers
Pull request: Add a check to import_utils.py to allow for use of faiss_gpu installation

# What does this PR do?
When using Transformers RagRetriever and Milvus in a jupyter notebook, the faiss library is required. I specifically need faiss-gpu, but as the check for this is not implemented here I am unable to run my code. 
This PR adds a check for faiss-gpu to the existing faiss and faiss-cpu checks. 
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Fixes # (issue)
Related to https://github.com/huggingface/transformers/issues/11720 - previously closed

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Changed files:
filename: src/transformers/utils/import_utils.py
patch: @@ -131,7 +131,7 @@ def _is_package_available(pkg_name: str, return_version: bool = False) -> Union[
 _yt_dlp_available = importlib.util.find_spec("yt_dlp") is not None
 _datasets_available = _is_package_available("datasets")
 _detectron2_available = _is_package_available("detectron2")
-# We need to check both `faiss` and `faiss-cpu`.
+# We need to check `faiss`, `faiss-cpu` and `faiss-gpu`.
 _faiss_available = importlib.util.find_spec("faiss") is not None
 try:
     _faiss_version = importlib.metadata.version("faiss")
@@ -141,7 +141,11 @@ def _is_package_available(pkg_name: str, return_version: bool = False) -> Union[
         _faiss_version = importlib.metadata.version("faiss-cpu")
         logger.debug(f"Successfully imported faiss version {_faiss_version}")
     except importlib.metadata.PackageNotFoundError:
-        _faiss_available = False
+        try:
+            _faiss_version = importlib.metadata.version("faiss-gpu")
+            logger.debug(f"Successfully imported faiss version {_faiss_version}")
+        except importlib.metadata.PackageNotFoundError:
+            _faiss_available = False
 _ftfy_available = _is_package_available("ftfy")
 _g2p_en_available = _is_package_available("g2p_en")
 _hadamard_available = _is_package_available("fast_hadamard_transform")