@datastore_rpc.ConfigOption
  def limit(value):
    datastore_types.ValidateInteger(value,
                                    'limit',
                                    datastore_errors.BadArgumentError,
                                    zero_ok=True)
    return value
Test the product filtering of the readout.
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/datastore/datastore_query.py/QueryOptions.limit--crossover with--dataset/ETHPy150Open mozilla/kitsune/kitsune/dashboards/tests/test_readouts.py/UnreadyTests.test_by_product