The point is, with Django you'd have to painstakingly reverse-engineer a Django Model from your existing database. sandman does all of this without writing any boilerplate code (aside from listing the names of the tables you want included in your API).
The difference in LOC and general frustration is huge.
I agree that is extremely awesome. I was just responding to his question. I have already started playing with your project, and have enjoyed experimenting with it.
admin.site.register(ModelName)
Django documentation for this: https://docs.djangoproject.com/en/dev/ref/contrib/admin/