title: How to construct GQL to not contain a value from a set?
body: <p>Is it possible to select from a google app engine db where the key of a <code>db.Model</code> object is not in a given list?  If so, what would be the syntax?</p>
  
  <p>Ex of a model class:</p>
  
  <pre><code>class Spam(db.Model):
      field1 = db.BooleanProperty(default=false)
      field2 = db.IntegerProperty()
  </code></pre>
  
  <p>Example of a query which I'd like to work but can't figure out:</p>
  
  <pre><code>spam_results = db.GqlQuery(
  "SELECT * FROM Spam WHERE key NOT IN :1 LIMIT 10", 
  ['ag1waWNreXByZXNlbnRzchMLEgxBbm5vdW5jZW1lbnQYjAEM', 
   'ag1waWNreXByZXNlbnRzchMLEgxBbm5vdW5jZW1lbnQYjgEM'])
  
  for eggs in spam_results:
    print "id: %s" % a.key().id()
  </code></pre>