Update app.py

app.py

@@ -13,7 +13,7 @@ else:
 try:
   lang = langcodes.Language.get(langtext)
   st.write(f"{lang} is the BCP-47 tag.")
-  if "unknown" in lang.display_name().to_lower():
+  if "unknown" in lang.display_name().lower():
     lang = None
 except langcodes.LanguageTagError as e: 
   st.write(f"Could not simply instantiate, trying to look up instead.")