Update Gradio_UI.py

Gradio_UI.py

@@ -151,6 +151,8 @@ def launch_step_by_step_ui():
 
             if not file_path:
                 file_path = None
+            if file_path is None:
+                file_path = ""
             return messages, updated_state, file_path
 
         def restart_conversation():