Update app.py

app.py

@@ -3,6 +3,7 @@
 # https://www.stockfish.online/docs.php (API)
 # https://www.stockfish.online/ (FEN to image)
 
+import re
 import gradio as gr
 import gradio.utils, requests
 from typing import Optional, List, Dict, Any
@@ -18,11 +19,11 @@ def position_evaluation(fen):
     Returns:
         tuple: (result, error) - Best move with continuation in UCI notation
     """
-    is_valid, err_msg = validate_input(fen)
+    is_valid, msg = validate_input(fen)
     
     if not is_valid:
-        gr.Warning(f"Invalid input: {err_msg}")
-        return None, err_msg
+        gr.Warning(f"Invalid input: {msg}")
+        return None, msg
     
     print("")