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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def __select_subfeatures (parent_property, features):
 """ Given a property, return the subset of features consisting of all ordinary subfeatures of the property's feature, and all specific subfeatures of the property's feature which are conditional on the property's value. """

    if __debug__:
        from .property import Property
        assert isinstance(parent_property, Property)
        assert is_iterable_typed(features, Feature)
    return [f for f in features if is_subfeature_of (parent_property, f)]