'Update the index for a single object. Attached to the class\'s
post-save hook.
If ``using`` is provided, it specifies which connection should be
used. Default relies on the routers to decide which backend should
be used.'

def update_object(self, instance, using=None, **kwargs):

    if self.should_update(instance, **kwargs):
        backend = self.get_backend(using)
        if (backend is not None):
            backend.update(self, [instance])
