python - Exception occurred processing WSGI script - IOError: failed to write data -

i'm trying save image @ server side.i recieve base64 string decode first , save in database.however failed, checked server error log , found following error.log

    [tue may 21 14:26:38 2013] [error] [client 41.236.182.133] mod_wsgi (pid=4952): exception occurred processing wsgi script '/root/ar_browser/example/wsgi.py'. [tue may 21 14:26:38 2013] [error] [client 41.236.182.133] ioerror: failed write data 

i checked wsgi.py

import os import sys  path = '/root/ar_browser/example'  sys.path.append('/root/ar_browser/example') sys.path.append('/root/ar_browser') sys.path.append('/root/ar_browser/example/app')  os.environ['django_settings_module'] = 'settings'  import django.core.handlers.wsgi application = django.core.handlers.wsgi.wsgihandler() 

but can't find wrong. idea cause of issue?! code responsible saving image

 @csrf_exempt         def create_app(request):         appname = request.post['name']         user = request.post['userid']         c = request.post['category']         = request.post['image']         imgdata = base64.b64decode(i)         t = datetime.now()         filename = t.strftime('test.jpg')           open(filename, 'w') f:             f.write(imgdata)             f.close()         u=app_user.objects.get(id=user)         apps = app.objects.create(name = appname, category=c, user_id = u.id, app_logo=file(filename))         apps.save()          return httpresponse("you created %s." % apps.name) 

that message mod_wsgi no traceback means http client closed connection before response data written mod_wsgi.