ValueError: max() arg is an empty sequence

[fundwotsai2001]

First of all, thanks for your interesting work, but now I meet a strange bug.
`import chorderator as cdt

if name == 'main':

demo_name = 'hpps65'
input_melody_path = '/home/fundwotsai/EMO_Harmonizer/小手拉大手-梁靜茹-130-C大调.mid'

cdt.set_melody(input_melody_path)
cdt.set_meta(tonic=cdt.Key.C, mode=cdt.Mode.MAJOR)
cdt.set_segmentation('A8B8A8B8A8B8')
cdt.set_texture_prefilter((0, 2))
cdt.set_note_shift(64)
cdt.set_output_style(cdt.Style.POP_STANDARD)
cdt.generate_save(demo_name + '_output_results')

`
I would like to know the reason for this issue! Thanks.
https://drive.google.com/file/d/1g9a9D7CcL2VJVlmz9vq3h6heGjWZbDKV/view?usp=drive_link