change additional_args's default value to None

app.py

@@ -64,7 +64,7 @@ class BasicAgent:
         )
         print("BasicAgent initialized.")
         
-    def __call__(self, question: str, additional_args: dict = {}) -> str:
+    def __call__(self, question: str, additional_args: dict | None) -> str:
         print(f"Agent received question (first 50 chars): {question[:50]}...")
         answer = self.agent.run(task=question, additional_args=additional_args)
         print(f"Agent returning answer: {answer}")
@@ -128,7 +128,7 @@ def run_and_submit_all( profile: gr.OAuthProfile | None):
         task_id = item.get("task_id")
         question_text = item.get("question")
 
-        file_info = {}
+        file_info = None
 
         if item.get("file_name"):
             file_name = item.get("file_name")