A Manager is the interface through which database query operations are provided to Django models. At least one Manager exists for every model in a Django application.
By default, Django adds a Manager with the name objects to every Django model class
这个好像偷换了不同的概念了。
User(id=2),是创建一个User实例, 然后User中的id=2。这个需要save()才能把数据存放到数据库里。
User.objects.get(id=2),才是去查找User表里的数据。这个返回是数据库的数据。
Django Office docs: