Python-сообщество

admin.py
class AdminImageWidget(AdminFileWidget):
    def render(self, name, value, attrs=None):
        output = []
        if value and hasattr(value, "url"):
            obj = Image.objects.get(image=value)
            output.append(('<a target="_blank" href="%s"><img src="%s"></a>' % (value.url, obj.thumbnail.url)))
        output.append(super(AdminImageWidget, self).render(name, value, attrs))
        return mark_safe(u''.join(output))
class ImageInline(admin.StackedInline):
    model = Image
    formfield_overrides = {
        models.ImageField: {'widget': AdminImageWidget},
    }