Python openpyxl 无法保存文件的解决方案

[root@billig mytest]# pip install openpyxl==2.5.11
DEPRECATION: Python 2.7 will reach the end of its life on January 1st, 2020. Please upgrade your Python as Python 2.7 won't be maintained after that date. A future version of pip will drop support for Python 2.7.
Looking in indexes: http://mirrors.aliyun.com/pypi/simple/
Collecting openpyxl==2.5.11
 Downloading http://mirrors.aliyun.com/pypi/packages/38/7f/65d6b1700470749579b1585bbaf85fb8885f10fd53a77fb11915df913bbc/openpyxl-2.5.11.tar.gz (173kB)
  100% |################################| 174kB 596kB/s
Requirement already satisfied: jdcal in /usr/lib/python2.7/site-packages (from openpyxl==2.5.11) (1.4)
Requirement already satisfied: et_xmlfile in /usr/lib/python2.7/site-packages (from openpyxl==2.5.11) (1.0.1)
Installing collected packages: openpyxl
 Found existing installation: openpyxl 2.5.14
  Uninstalling openpyxl-2.5.14:
   Successfully uninstalled openpyxl-2.5.14
 Running setup.py install for openpyxl ... done
Successfully installed openpyxl-2.5.11

raceback (most recent call last):
 File "excelwritedemonopd.py", line 24, in <module>
  work_book.save("demo_new.xlsx")
 File "/usr/lib/python2.7/site-packages/openpyxl/workbook/workbook.py", line 391, in save
  save_workbook(self, filename)
 File "/usr/lib/python2.7/site-packages/openpyxl/writer/excel.py", line 284, in save_workbook
  writer.save(filename)
 File "/usr/lib/python2.7/site-packages/openpyxl/writer/excel.py", line 266, in save
  self.write_data()
 File "/usr/lib/python2.7/site-packages/openpyxl/writer/excel.py", line 85, in write_data
  self._write_images()
 File "/usr/lib/python2.7/site-packages/openpyxl/writer/excel.py", line 122, in _write_images
  self._archive.writestr(img.path[1:], img._data())
 File "/usr/lib/python2.7/site-packages/openpyxl/drawing/image.py", line 64, in _data
  img = _import_image(self.ref)
 File "/usr/lib/python2.7/site-packages/openpyxl/drawing/image.py", line 33, in _import_image
  img = PILImage.open(img)
 File "/usr/lib64/python2.7/site-packages/PIL/Image.py", line 2638, in open
  fp.seek(0)
ValueError: I/O operation on closed file.