Update app.py

added type hints to get_file function

app.py

@@ -56,7 +56,7 @@ class BasicAgent:
         # return answer.text
 
     @tool
-    def get_file(self, task_id):
+    def get_file(self, task_id: str) -> IO:
         '''
         Downloads the file associated with the given task_id, if one exists and is mapped.
         If the question mentions an attachment, use this function.