def METHOD_NAME(self):
    PostPlaceholderExtension.objects.all().delete()
    djangocms_blog.admin.register_extension(PostPlaceholderExtension)
    post = self._get_post(self._post_data[0]["en"])
    PostPlaceholderExtension.objects.get(post=post)
    post.delete()
    djangocms_blog.admin.unregister_extension(PostPlaceholderExtension)