def nin(self, *values):
        ''' A query to check if this query field is not one of the values
            in ``values``.  Produces a MongoDB ``$nin`` expression.
        '''
        return QueryExpression({
            self : { '$nin' : [self.get_type().wrap_value(value) for value in values] }
        })
A query to check if this query field is not one of the values
            in ``values``.  Produces a MongoDB ``$nin`` expression.