Show image thumbnail in django admin

Question

I'm trying to display image thumbnail in my admin but I get

<img src="/media/photos/huyase_18638553_orig_.jpeg" width=60 height=60 />

but not the image. My model:

class RentPhoto(models.Model):
    '''
    Photos for RentItem
    Only one photo could be avatar photo
    '''
    photo = models.ImageField(_('Photo'), upload_to='photos/')
    is_avatar = models.BooleanField(_('Avatar'), default=False)
    rentitem = models.ForeignKey(RentItem, related_name='photo')
    description = models.CharField(_('Description'), max_length=250)

    def thumb(self):
        if self.photo:
            return u'<img src="%s" width=60 height=60 />' % (self.photo.url)
        else:
            return u'No image file found'
    thumb.short_description = _('Thumbnail')

My admin.py:

class RentPhotoAdmin(admin.ModelAdmin):
    fields = ('photo', 'is_avatar', 'rentitem', 'description')
    list_display = ('thumb', 'rentitem', 'is_avatar', 'description')

admin.site.register(RentPhoto, RentPhotoAdmin)

I also added

(r'^public/(?P<path>.*)$', 'django.views.static.serve', {
    'document_root': settings.MEDIA_ROOT}),

to my urls.py. When I go to 127.0.0.1:8000/media/photos/huyase_18638553_orig_.jpeg I can see image. It's ok. What could be wrong?
P.S. I use django-grapelli for my admin site. Could it break my images?

Answer 1

You need to mark the html returned by the thumb method as safe. Use mark_safe