Update app.py

app.py

@@ -213,7 +213,7 @@ def MixMelody(input_midi, input_find_best_match):
             
             else:
 
-                if i < len(cscore)
+                if i < len(cscore):
                     next_note_dtime = cscore[i+1][0][1] - cscore[i][0][1]
                 
                 mixed_song.extend(mix_chord(cho, src_harm_tones_chords[midx], trg_patch, src_melody_pitches[midx], next_note_dtime))