python - Google App Engine: how can I programmatically access the properties of my Model class?

Question

I have a model class:

class Person(db.Model):
  first_name = db.StringProperty(required=True)
  last_name = db.StringProperty(required=True)

I have an instance of this class in p, and string s contains the value 'first_name'. I would like to do something like:

print p[s]

and

p[s] = new_value

Both of which result in a TypeError.

Does anybody know how I can achieve what I would like?

Answer 1

Waitting for answers