def __init__(self, features, version=None, stats=None):
        self.features = tuple(features)
        self.version = version
Check if the extension is valid.
dataset/ETHPy150Open wiki-ai/revscoring/revscoring/scorer_models/scorer_model.py/ScorerModel.__init__--crossover with--dataset/ETHPy150Open moloney/dcmstack/src/dcmstack/dcmmeta.py/DcmMetaExtension.check_valid