CreateView-尝试保存图像上载时出现TypeError

我试着把我的脑袋放在图像上 Form handling with class-based views . 所以我在玩这个简单的模型。使用CreateView时,我是否必须使用form_类用自定义表单覆盖它才能成功上载/保存和图像?

我不明白为什么我会这样:

Exception Type:     TypeError
Exception Value:    expected str, bytes or os.PathLike object, not tuple

整个东西都是赤裸裸的,没有存货。

模型。py公司

class Post(models.Model):
    headline = models.CharField(max_length=80, blank=True, null=True)
    cover_image = models.ImageField('hero image', upload_to='images/', blank=True, null=True)
    slug = models.SlugField(max_length=80, blank=True, null=True, unique=True)

    def get_absolute_url(self):
        return reverse('details', args=[str(self.slug)])

意见。py公司

from django.contrib.auth.mixins import LoginRequiredMixin
from django.views.generic import CreateView

class PostCreateView(LoginRequiredMixin, CreateView):
    model = Post
    fields = ['headline', 'cover_image', 'slug']

新闻/模板/新闻/post_表单。py公司

<form enctype="multipart/form-data" method="post" action="">
    {% csrf_token %}
    {{ form.as_p }}
    <input type="submit" value="Save"/>
  </form>

有人能帮我理解吗?

按要求

# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/2.0/howto/static-files/

STATIC_URL = '/static/'

STATICFILES_DIRS = (os.path.join(BASE_DIR, 'static'),)

MEDIA_ROOT = (os.path.join(BASE_DIR, 'media'),)
MEDIA_URL = '/media/'

LOGIN_REDIRECT_URL = 'home'