gistfile1.py

_CLASSNAME = None
def _createDefaultNo():
    bloggers = _CLASSNAME.all().fetch(1000)
    if len(bloggers) == 0:
        return 1
    else:
        return max(bloggers, key=lambda x:x.no).no + 1

class Blogger(db.Model):
    no = db.IntegerProperty(required=True, default=_createDefaultNo)
    name = db.StringProperty(required=True)
    date_created = db.DateTimeProperty(auto_now_add=True)

    def __unicode__(self):
        return '%2d - %s' % (self.no, self.name)
_CLASSNAME = Blogger