Update app.py

app.py

@@ -206,4 +206,7 @@ def demo():
             outputs=[chatbot, doc_source1, source1_page, doc_source2, source2_page, doc_source3, source3_page], \
             queue=False)
     demo.queue().launch(debug=True)
+
+if __name__ == "__main__":
+    demo()