diff --git a/examples/ags/benchmark/humaneval.py b/examples/ags/benchmark/humaneval.py
index 62b062ae0..ec1a3402d 100644
--- a/examples/ags/benchmark/humaneval.py
+++ b/examples/ags/benchmark/humaneval.py
@@ -74,7 +74,7 @@ async def samples_generate(mode: ModeType, result_path: str = "samples.jsonl"):
     async def solve_and_write(id: str, mode: ModeType) -> Optional[str]:
         try:
             sample_dict = await route_generate(mode, id)
-        except Exception as e:
+        except Exception:
             return id
         async with file_lock:
             async with aiofiles.open(result_path, mode="a") as f:
diff --git a/metagpt/utils/common.py b/metagpt/utils/common.py
index dfb616da4..47f2768cd 100644
--- a/metagpt/utils/common.py
+++ b/metagpt/utils/common.py
@@ -602,7 +602,7 @@ def add_jsonl_file(jsonl_file: str, data: list[dict], encoding: str = None):
 
     with open(jsonl_file, "a", encoding=encoding) as fout:
         for json_item in data:
-            fout.write(json.dumps(json_item) + '\n')
+            fout.write(json.dumps(json_item) + "\n")
 
 
 def read_csv_to_list(curr_file: str, header=False, strip_trail=True):