Enhance check_format function to flatten nested lists and raise error for dict inputs

app.py

@@ -51,10 +51,22 @@ def check_format(answer: str | list, *args, **kwargs ) -> list:
     """ Check if the answer is a list. """
     
     print("Checking format of the answer:", answer)
-    if isinstance(answer, list):
-        return answer
-    else:
-        return [answer]
+    def flatten(lst):
+        for item in lst:
+            if isinstance(item, list):
+                yield from flatten(item)
+            else:
+                yield item
+    try:
+        if isinstance(answer, list):
+            flat = list(flatten(answer))
+            return flat
+    except Exception as e:
+        if isinstance(answer, dict):
+            raise TypeError(f"Final answer must be a list, not a dict. Please check the answer format. Error: {e}")
+        
+        
+
     
 
 ## tools definition