如何在Django表单中为新用户设置站点权限

我在Django/Mezzanine项目中有这样的课程：

class SitePermission(models.Model):
    """
    Permission relationship between a user and a site that's
    used instead of ``User.is_staff``, for admin and inline-editing
    access.
    """

    user = models.OneToOneField(user_model_name, verbose_name=_("Author"),
        related_name="%(class)ss")
    sites = models.ManyToManyField("sites.Site", blank=True,
                                   verbose_name=_("Sites"))

    class Meta:
        verbose_name = _("Site permission")
        verbose_name_plural = _("Site permissions")

在管理中选择一个站点并按下保存按钮时。记录将访问具有权限的数据库

如何在前端执行以下操作：

def create_site(request):
    if request.method == "POST":
        form = CreateSite(request.POST)
        if form.is_valid():
            try:
                post = form.save(commit=False)
                post.save()
                return HttpResponseRedirect('/welcome/')
            except IntegrityError:
                form._errors["domain"] = ["Domain must be unique!"]
    else:
        form = CreateSite()
    return render(request, "includes/create_site.html", {'form': form})

class CreateSite(ModelForm):
    class Meta:
        model = Site
        fields = ['domain' , 'name']

创建新站点+用户（以相同的形式）

创建新站点（子域）作为用户名。就像是同一个输入表单

将站点权限添加到新创建的用户

添加站点标题

在此之后添加更多用户名数据

这是我当前处理此问题的视图：

def create_site(request):
    if request.method == "POST":
        form = CreateSite(request.POST)
        if form.is_valid():
            try:
                post = form.save(commit=False)
                post.save()
                return HttpResponseRedirect('/welcome/')
            except IntegrityError:
                form._errors["domain"] = ["Domain must be unique!"]
    else:
        form = CreateSite()
    return render(request, "includes/create_site.html", {'form': form})

class CreateSite(ModelForm):
    class Meta:
        model = Site
        fields = ['domain' , 'name']

forms.py:

def create_site(request):
    if request.method == "POST":
        form = CreateSite(request.POST)
        if form.is_valid():
            try:
                post = form.save(commit=False)
                post.save()
                return HttpResponseRedirect('/welcome/')
            except IntegrityError:
                form._errors["domain"] = ["Domain must be unique!"]
    else:
        form = CreateSite()
    return render(request, "includes/create_site.html", {'form': form})

class CreateSite(ModelForm):
    class Meta:
        model = Site
        fields = ['domain' , 'name']