我正在按照本教程在我的Django项目中创建一个视频上传程序，但遇到了以下错误:

。。src/video/views.py“，第9行，showvideo Videofile=LastVideo.Videofile AttributeError:”NoneType“对象没有属性”videofile“

我肯定我错过了一些显而易见的东西，现在已经在寻找答案有一阵子了。 如果有任何帮助，我将不胜感激。

views.py

from django.shortcuts import render
from .models import VideoUpload
from .forms import VideoForm

def showvideo(request):

    lastvideo= VideoUpload.objects.last()

    videofile= lastvideo.videofile


    form= VideoForm(request.POST or None, request.FILES or None)
    if form.is_valid():
        form.save()


    context= {'videofile': videofile,
              'form': form
              }


    return render(request, 'video.html', context)

forms.py

from django import forms
from .models import VideoUpload


class VideoForm(forms.ModelForm):

    class Meta:
        model = VideoUpload
        fields = ["name", "videofile"]

models.py

from django.db import models

class VideoUpload(models.Model):
    name= models.CharField(max_length=500)
    videofile= models.FileField(upload_to='videos/', null=True, verbose_name="")

    def __str__(self):
        return self.name + ": " + str(self.videofile)

from django.conf import settings 
from django.contrib import admin
from django.urls import path
from django.conf.urls.static import static

from video.views import (
    showvideo,
)

urlpatterns = [
    path('showvideo', showvideo, name='showvideo'),
]

if settings.DEBUG:
 urlpatterns += static(settings.STATIC_URL, document_root=settings.STATIC_ROOT)
 urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)

供参考，我更新了模型的名称为'videoupload'vs教程。