ValueError: I/O operation on closed file

原始代码：

with pd.ExcelWriter(
        saver + '\\' + spectral_wind_profile.out_name + datetime.now().strftime(
            '%m%d%H%M') + '_廓线分类结果.xlsx') as writer:
    df_10min_1.to_excel(writer, sheet_name='wind speed')
    df_Par.to_excel(writer, sheet_name='Parameters')
    df_Par_percentage.to_excel(writer, sheet_name='percentage')

writer.save()
writer.close()
return site_name

multiprocessing.pool.RemoteTraceback: 
"""
Traceback (most recent call last):
    writer.save()
  File "D:\ProgramData\Anaconda3\lib\site-packages\pandas\io\excel\_openpyxl.py", line 81, in save
    self.book.save(self.handles.handle)
  File "D:\ProgramData\Anaconda3\lib\site-packages\openpyxl\workbook\workbook.py", line 386, in save
    save_workbook(self, filename)
  File "D:\ProgramData\Anaconda3\lib\site-packages\openpyxl\writer\excel.py", line 291, in save_workbook
    archive = ZipFile(filename, 'w', ZIP_DEFLATED, allowZip64=True)
  File "D:\ProgramData\Anaconda3\lib\zipfile.py", line 1275, in __init__
    self.start_dir = self.fp.tell()
ValueError: I/O operation on closed file

修改后代码：

with pd.ExcelWriter(
        saver + '\\' + spectral_wind_profile.out_name + datetime.now().strftime(
            '%m%d%H%M') + '_廓线分类结果.xlsx') as writer:
    df_10min_1.to_excel(writer, sheet_name='wind speed')
    df_Par.to_excel(writer, sheet_name='Parameters')
    df_Par_percentage.to_excel(writer, sheet_name='percentage')

	writer.save()
	writer.close()
	return site_name