app.py: old signature request

app.py

@@ -105,10 +105,13 @@ def main():
         with gr.Row():
             result_audio = gr.Audio()
 
-        def voice_conversion(src_from_mic_, src_from_file_, tgt_from_file_, api_key_, api_secret_, request_: gr.Request):
+        def voice_conversion(src_from_mic_, src_from_file_, tgt_from_file_, api_key_=None, api_secret_=None, request_: gr.Request=None):
             """
             helper function which checks where source come from
             """
+            if api_key_ is None and api_secret_ is None and request_ is None:
+                logging.warning("Old signature request")
+                return
             src_ = None
             if src_from_mic_:
                 src_ = src_from_mic_