小编use*_*424的帖子

我收到错误"CrystalDecisions.CrystalReports.Engine.dll"丢失.从哪里可以下载DLL.我已经安装了sap CrystalDecisions但是它给出了同样的问题

当我尝试登录我的仪表板时，Django 1.10 出错。

回溯（最近一次调用最后一次）：

 File "/Users/guest/epifiction/lib/python2.7/site-packages/django/core/handlers/exception.py", line 39, in inner
response = get_response(request)

 File "/Users/guest/epifiction/lib/python2.7/site-packages/django/core/handlers/base.py", line 187, in _get_response
response = self.process_exception_by_middleware(e, request)

 File "/Users/guest/epifiction/lib/python2.7/site-packages/django/core/handlers/base.py", line 185, in _get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)

 File "/Users/guest/epifiction/lib/python2.7/site-packages/django/views/decorators/cache.py", line 58, in _wrapped_view_func
add_never_cache_headers(response)

 File "/Users/guest/epifiction/lib/python2.7/site-packages/django/utils/cache.py", line 230, in add_never_cache_headers
patch_response_headers(response, cache_timeout=-1)

  File "/Users/guest/epifiction/lib/python2.7/site-packages/django/utils/cache.py", line 219, in patch_response_headers
if not response.has_header('Last-Modified'):

AttributeError: 'NoneType' 对象没有属性 'has_header'

这是查看代码

class AuthorLoginView(bracesviews.AnonymousRequiredMixin,authviews.LoginView):
   form_class = forms.AuthorLoginForm
   template_name = 'landing_page/demo.html'

 def form_valid(self, form):
    username = form.cleaned_data.get('username')
    userId = User.objects.get(username=username).id …