fix unknown language error

app.py

@@ -139,7 +139,7 @@ def textclassification(SubmittedText):
     if language == "fr":
         SubmittedText = translate_to_de(SubmittedText)
     elif language != "de":
-        return UNKNOWN_LANG_TEXT, None
+        return UNKNOWN_LANG_TEXT, None, None, None
 
     # Make the prediction with the 1000 first characters
     images = []