Update app.py

app.py

@@ -80,6 +80,7 @@ with gr.Blocks() as chat_interface:
         new_subcategories = categories.get(selected_main_category, [])
         return gr.Dropdown.update(choices=new_subcategories, value=new_subcategories[0] if new_subcategories else None)
 
+    # Handle main category change to update subcategories
     main_category.change(update_subcategories, inputs=main_category, outputs=sub_category)
 
     with gr.Row():