code: 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] }
          }f 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] }
          })
docs: A query to check if this query field is not one of the values
              in ``values``.  Produces a MongoDB ``$nin`` expression.