backends.py 文件源码

def authenticate(self, request, facebook_id):
        username = '{}_{}_{}'.format(
            User.USER_TYPE_FACEBOOK,
            settings.FACEBOOK_APP_ID,
            facebook_id,
        )
        try:
            user = User.objects.get(
                user_type=User.USER_TYPE_FACEBOOK,
                username=username
            )
            return user
        except User.DoesNotExist:
            return None