Если расписывать полную ошибку, то
line 36, in
wb = openpyxl.load_workbook(wb)
line 147, in load_workbook
archive = _validate_archive(filename)
line 97, in _validate_archive
archive = ZipFile(filename, 'r')
line 1269, in init
self._RealGetContents()
line 1332, in _RealGetContents
endrec = _EndRecData(fp)
line 264, in _EndRecData
fpin.seek(0, 2)