Update app.py

app.py

@@ -310,6 +310,7 @@ async def read_root(request: Request):
 async def restore_text(req: RestoreRequest) -> Dict[str, Any]:
     try:
         is_char = req.mode == "char"
+        mask    = "[MASK]" if is_char else tokenizer_bpe.mask_token
         bpe_mask = tokenizer_bpe.mask_token
         text    = req.text.replace("#", "[GAP]")