本人使用django1.11.16做了一个在线相册系统，现在想下载选中图片，想要?400报错

def send_zipfile(request):

20     """                                                                        

21     Create a ZIP file on disk and transmit it in chunks of 8KB,                

22     without loading the whole file into memory. A similar approach can         

23     be used for large dynamic PDF files.                                       

24     """

25     temp = tempfile.TemporaryFile()

26     archive = zipfile.ZipFile(temp, 'w', zipfile.ZIP_DEFLATED)

27     for index in range(10):

28         filename = __file__ # Select your files here.                          

29         archive.write(filename, 'file%d.txt' % index)

30     archive.close()

31     wrapper = FileWrapper(temp)

32     response = HttpResponse(wrapper, content_type='application/zip')

33     response['Content-Disposition'] = 'attachment; filename=test.zip'

34     response['Content-Length'] = temp.tell()

35     temp.seek(0)

36     return response

这里边我真是不懂archive.write(filename, 'file%d.txt' % index)为什么要加txt这句。

另外我运行就报错说是I/O调用关闭文件。求大神解答