Update app.py

app.py

@@ -147,7 +147,8 @@ Provide a concise, user-friendly interpretation of these findings in simple term
 # Step 1: Inspect file
 def preview_file(file):
     msg, cols, preview = inspect_file(file)
-    return msg, gr.Dropdown.update(choices=cols, value=None), preview
+    # Instead of gr.Dropdown.update(...)
+    return msg, {"choices": cols, "value": None}, preview
 
 with gr.Blocks() as demo:
     gr.Markdown("# NeuroNarrative-Lite: EEG Summary with Flexible Preprocessing")