Fix linting

lightrag/kg/oracle_impl.py

@@ -1,6 +1,5 @@
 import array
 import asyncio
-import os
 
 # import html
 # import os
@@ -326,7 +325,9 @@ class OracleVectorDBStorage(BaseVectorStorage):
         config = self.global_config.get("vector_db_storage_cls_kwargs", {})
         cosine_threshold = config.get("cosine_better_than_threshold")
         if cosine_threshold is None:
-            raise ValueError("cosine_better_than_threshold must be specified in vector_db_storage_cls_kwargs")
+            raise ValueError(
+                "cosine_better_than_threshold must be specified in vector_db_storage_cls_kwargs"
+            )
         self.cosine_better_than_threshold = cosine_threshold
 
     async def upsert(self, data: dict[str, dict]):