Django - 尝试用电子邮件来构思

Question

目标是发送包含当前登录用户关联名称的电子邮件，如下所示：

asoc_name@mail.com

我得到的错误是：

The annotation 'email' conflicts with a field on the model.

我尝试过改变现场和其他解决方案而没有运气。

真的很感谢你的帮助，伙计们！

Django：1.10
Python：3.6

views.py

class mailPost(FormView):
   success_url = '.'
   form_class = mailHandler
   template_name = 'post/post.html'

   def form_valid(self, form):
       messages.add_message(self.request, messages.SUCCESS, 'Email Sent!')
       return super(mailPost, self).form_valid(form)

   def form_invalid(self, form):
       messages.add_message(self.request, messages.WARNING,
                         'Email not sent. Please try again.')
       return super(mailPost, self).form_invalid(form)

   def post(self, request, *args, **kwargs):
       form_class = self.get_form_class()
       form = self.get_form(form_class)

       if form.is_valid():
          sender = Association.objects.filter(asoc_name=self.request.user.association).annotate(email=Concat('asoc_name', Value('@mail.com')))
           receiver = form.cleaned_data.get('receiver')
           subject = form.cleaned_data.get('subject')
           message = form.cleaned_data.get('message')
           time = datetime.now()
           asoc_pk = Association.objects.filter(asoc_name=self.request.user.association)
           asoc = Association.objects.get(id=asoc_pk)

           Email.objects.create(
               sender=sender,
               receiver=receiver,
               subject=subject,
               message=message,
               association=asoc,
               sentTime=time
           )

           msg = EmailMultiAlternatives(subject, message, sender, [receiver])
           msg.send()

           return self.form_valid(form)
       else:
           return self.form_invalid(form)

models.py

class Email(models.Model):
   sender = models.CharField(max_length=254)
   sentTime = models.DateTimeField(auto_now_add=True, blank=False)
   subject = models.CharField(max_length=254)
   receiver = models.CharField(max_length=254)
   cc = models.CharField(max_length=254)
   bcc = models.CharField(max_length=254)
   message = models.TextField()
   association = models.ForeignKey(Association)

   class Meta:
       db_table = 'Email'    


class Association(models.Model):
    asoc_name = models.CharField(max_length=50, null=True, blank=True, unique=True)


   class Meta:
       db_table = 'Association'