def METHOD_NAME(self):
    aggregator = WeightedPercentileAggregator()
    emsg = (
        "weighted_percentile aggregator requires "
        ".* keyword argument 'percent'"
    )
    with self.assertRaisesRegex(ValueError, emsg):
        aggregator.aggregate("dummy", axis=0, weights=None)
    emsg = (
        "weighted_percentile aggregator requires "
        ".* keyword argument 'weights'"
    )
    with self.assertRaisesRegex(ValueError, emsg):
        aggregator.aggregate("dummy", axis=0, percent=50)