Update app.py

app.py

@@ -112,7 +112,7 @@ with main:
                     song.addNote(0, 0, pitch, time, dur, 100)
                     if not notationIndex:
                         time += dur
-                with open(os.path.join(st.session_state['path'], 'output.mid'), 'wb') as f:
+                with open(os.path.join(st.session_state['path'], 'out.mid'), 'wb') as f:
                     song.writeFile(f)
                 if not st.session_state['downloadable']:
                     st.session_state['downloadable'] = True