def add_melody(self, melody, length):
        for note in melody:
            if '0123456789' not in note[-1]:
                note += self.octave
            self.add_wave(note_to_frequency(note), length)
dataset/ETHPy150Open jdan/Melopy/melopy/melopy.py/Melopy.add_melody/swapped operands of `not in`