diff --git a/lightrag/lightrag.py b/lightrag/lightrag.py
index a5cb3b22..48b464a8 100644
--- a/lightrag/lightrag.py
+++ b/lightrag/lightrag.py
@@ -1294,14 +1294,14 @@ class LightRAG:
     ):
         """
         Query with separate keyword extraction step.
-        
+
         This method extracts keywords from the query first, then uses them for the query.
-        
+
         Args:
             query: User query
             prompt: Additional prompt for the query
             param: Query parameters
-            
+
         Returns:
             Query response
         """
@@ -1315,12 +1315,12 @@ class LightRAG:
     ) -> str | AsyncIterator[str]:
         """
         Async version of query_with_separate_keyword_extraction.
-        
+
         Args:
             query: User query
             prompt: Additional prompt for the query
             param: Query parameters
-            
+
         Returns:
             Query response or async iterator
         """
@@ -1336,7 +1336,7 @@ class LightRAG:
             global_config=asdict(self),
             hashing_kv=self.llm_response_cache,
         )
-        
+
         await self._query_done()
         return response
 
diff --git a/lightrag/operate.py b/lightrag/operate.py
index 95a5c72e..1815f308 100644
--- a/lightrag/operate.py
+++ b/lightrag/operate.py
@@ -1917,6 +1917,7 @@ async def kg_query_with_keywords(
 
     return response
 
+
 async def query_with_keywords(
     query: str,
     prompt: str,
@@ -1931,11 +1932,11 @@ async def query_with_keywords(
 ) -> str | AsyncIterator[str]:
     """
     Extract keywords from the query and then use them for retrieving information.
-    
+
     1. Extracts high-level and low-level keywords from the query
     2. Formats the query with the extracted keywords and prompt
     3. Uses the appropriate query method based on param.mode
-    
+
     Args:
         query: The user's query
         prompt: Additional prompt to prepend to the query
@@ -1947,7 +1948,7 @@ async def query_with_keywords(
         text_chunks_db: Text chunks storage
         global_config: Global configuration
         hashing_kv: Cache storage
-        
+
     Returns:
         Query response or async iterator
     """
diff --git a/lightrag/utils.py b/lightrag/utils.py
index 1143b326..b8f00c5d 100644
--- a/lightrag/utils.py
+++ b/lightrag/utils.py
@@ -891,6 +891,7 @@ def lazy_external_import(module_name: str, class_name: str) -> Callable[..., Any
 
     return import_class
 
+
 def get_content_summary(content: str, max_length: int = 100) -> str:
     """Get summary of document content
 
@@ -906,6 +907,7 @@ def get_content_summary(content: str, max_length: int = 100) -> str:
         return content
     return content[:max_length] + "..."
 
+
 def clean_text(text: str) -> str:
     """Clean text by removing null bytes (0x00) and whitespace
 
@@ -917,6 +919,7 @@ def clean_text(text: str) -> str:
     """
     return text.strip().replace("\x00", "")
 
+
 def check_storage_env_vars(storage_name: str) -> None:
     """Check if all required environment variables for storage implementation exist
 
@@ -927,7 +930,7 @@ def check_storage_env_vars(storage_name: str) -> None:
         ValueError: If required environment variables are missing
     """
     from lightrag.kg import STORAGE_ENV_REQUIREMENTS
-    
+
     required_vars = STORAGE_ENV_REQUIREMENTS.get(storage_name, [])
     missing_vars = [var for var in required_vars if var not in os.environ]
 
@@ -935,4 +938,4 @@ def check_storage_env_vars(storage_name: str) -> None:
         raise ValueError(
             f"Storage implementation '{storage_name}' requires the following "
             f"environment variables: {', '.join(missing_vars)}"
-        )
\ No newline at end of file
+        )