老师，我执行train.py 后出现以下代码提示，
最后一句提示是： IndexError: list index out of range
请问这中情况我应该如何修改代码呢？

Traceback (most recent call last):
File “train.py”, line 83, in
train()
File “train.py”, line 16, in train
notes = get_notes()
File “/home/jinhua/mooc/MusicAI/utils.py”, line 29, in get_notes
stream = converter.parse(file)
File “/home/jinhua/tensorflow/local/lib/python2.7/site-packages/music21/converter/init.py”, line 1110, in parse
forceSource=forceSource, **keywords)
File “/home/jinhua/tensorflow/local/lib/python2.7/site-packages/music21/converter/init.py”, line 998, in parseFile
v.parseFile(fp, number=number, format=format, forceSource=forceSource, **keywords)
File “/home/jinhua/tensorflow/local/lib/python2.7/site-packages/music21/converter/init.py”, line 533, in parseFile
self.parseFileNoPickle(fp, number, format, forceSource, **keywords)
File “/home/jinhua/tensorflow/local/lib/python2.7/site-packages/music21/converter/init.py”, line 467, in parseFileNoPickle
self.subConverter.parseFile(fp, number=number, **keywords)
File “/home/jinhua/tensorflow/local/lib/python2.7/site-packages/music21/converter/subConverters.py”, line 919, in parseFile
midiTranslate.midiFilePathToStream(fp, self.stream, **keywords)
File “/home/jinhua/tensorflow/local/lib/python2.7/site-packages/music21/midi/translate.py”, line 1952, in midiFilePathToStream
return midiFileToStream(mf, inputM21, **keywords)
File “/home/jinhua/tensorflow/local/lib/python2.7/site-packages/music21/midi/translate.py”, line 2093, in midiFileToStream
**keywords)
File “/home/jinhua/tensorflow/local/lib/python2.7/site-packages/music21/midi/translate.py”, line 1881, in midiTracksToStreams
p = s.getElementsByClass(‘Stream’)[0]
File “/home/jinhua/tensorflow/local/lib/python2.7/site-packages/music21/stream/iterator.py”, line 318, in getitem
e = fe[k]
IndexError: list index out of range