Update app.py

app.py

@@ -64,6 +64,6 @@ with gr.Blocks() as demo:
     play_button = gr.Button("Play MIDI")
     output = gr.HTML(elem_id="midi_visualizer_container")
     out = gr.Audio(label=" output")
-    play_button.click(play_midi, inputs=midi_file, outputs=output,out)
+    play_button.click(play_midi, inputs=[midi_file], outputs=[output,out])
 
 demo.launch()