Django(Python)AttributeError：’NoneType’对象没有属性’spli

Traceback (most recent call last):
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libwsgirefhandlers.py",line 138,in run
    self.finish_response()
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libwsgirefhandlers.py",line 180,in finish_response
    self.write(data)
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libwsgirefhandlers.py",line 279,in write
    self._write(data)
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libwsgirefhandlers.py",line 453,in _write
    self.stdout.write(data)
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libsocket.py",line 593,in write
    return self._sock.send(b)
ConnectionAbortedError: [WinError 10053] An established connection was aborted by the software in your host machine
[15/May/2016 13:50:09] "GET /media/uploads/Big_Buck_Bunny_Final.mp4 HTTP/1.1" 500 59

----------------------------------------

Exception happened during processing of request from ('127.0.0.1',23943)
[15/May/2016 13:50:09] "GET /static/image/video-poster.jpg HTTP/1.1" 304 0
Traceback (most recent call last):
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libwsgirefhandlers.py",in write
    return self._sock.send(b)
ConnectionAbortedError: [WinError 10053] An established connection was aborted by the software in your host machine

During handling of the above exception,another exception occurred:

Traceback (most recent call last):
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libwsgirefhandlers.py",line 141,in run
    self.handle_error()
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libsite-packagesdjangocoreserversbasehttp.py",line 92,in handle_error
    super(ServerHandler,self).handle_error()
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libwsgirefhandlers.py",line 368,in handle_error
    self.finish_response()
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libwsgirefhandlers.py",line 274,in write
    self.send_headers()
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libwsgirefhandlers.py",line 331,in send_headers
    if not self.origin_server or self.client_is_modern():
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libwsgirefhandlers.py",line 344,in client_is_modern
    return self.environ['SERVER_PROTOCOL'].upper() != 'HTTP/0.9'
TypeError: 'NoneType' object is not subscriptable

During handling of the above exception,another exception occurred:

Traceback (most recent call last):
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libsocketserver.py",line 628,in process_request_thread
    self.finish_request(request,client_address)
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libsocketserver.py",line 357,in finish_request
    self.RequestHandlerClass(request,client_address,self)
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libsite-packagesdjangocoreserversbasehttp.py",line 99,in __init__
    super(WSGIRequestHandler,self).__init__(*args,**kwargs)
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libsocketserver.py",line 684,in __init__
    self.handle()
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libsite-packagesdjangocoreserversbasehttp.py",line 179,in handle
    handler.run(self.server.get_app())
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libwsgirefhandlers.py",line 144,in run
    self.close()
  File "C:UsersSlavkoAppDataLocalProgramsPythonPython35-32libwsgirefsimple_server.py",line 35,in close
    self.status.split(' ',1)[0],self.bytes_sent
AttributeError: 'NoneType' object has no attribute 'split'

图像和视频的代码是相同的,这就是为什么我不明白这一点.
这是我的查看功能,当您访问帖子页面时使用：

def post_info(request,pk):
    form = CommentForm(request.POST or None)
    post = get_object_or_404(Post,pk=pk)
    same_author_posts = Post.objects.filter(author=post.author)
    if request.method == 'POST':
        if form.is_valid():
            instance = form.save(commit=False)
            instance.author = request.user
            instance.post = post
            instance.save()
            form = CommentForm()
            messages.success(request,'Comment is approved!')
            return HttpResponseRedirect('/post/%s/'%(pk))
        else:
            messages.error(request,'Comment is not valid!')
            return HttpResponseRedirect('/post/%s/'%(pk))
    context = {
        'form': form,'post': post,'same_author_posts': same_author_posts,}
    return render(request,'post/post_info.html',context)

可能它在响应中有状态代码,但为什么它不会在加载图像时显示它以及如何修复它？