如何使用python django中的OnetoOneField()将头像单独上传到user_auth？

from django.db import models
from django.contrib.auth.models import User

class UserProfile(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE)
    avatar = models.ImageField(upload_to='avatars/', null=True, blank=True)

    def __str__(self):
        return self.user.username

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

from django.conf import settings
from django.conf.urls.static import static

urlpatterns = [
    # ... 其他URL配置 ...
]

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

from django.shortcuts import render, redirect
from .models import UserProfile
from .forms import UserProfileForm

def upload_avatar(request):
    user_profile, created = UserProfile.objects.get_or_create(user=request.user)
    if request.method == 'POST':
        form = UserProfileForm(request.POST, request.FILES, instance=user_profile)
        if form.is_valid():
            form.save()
            return redirect('profile_detail')
    else:
        form = UserProfileForm(instance=user_profile)
    return render(request, 'upload_avatar.html', {'form': form})

from django import forms
from .models import UserProfile

class UserProfileForm(forms.ModelForm):
    class Meta:
        model = UserProfile
        fields = ['avatar']

<!-- upload_avatar.html -->
<form method="post" enctype="multipart/form-data">
    {% csrf_token %}
    {{ form.as_p }}
    <button type="submit">上传头像</button>
</form>