pub fn prop010_set_strategy(&self) -> impl Strategy<Value = FeatureSet<'g>> + 'g {
        let this = *self;
        fixedbitset_strategy(self.feature_count())
            .prop_map(move |included| FeatureSet::from_included(this, included))
    }
Returns a `Strategy` that generates random feature sets from this graph.
guppy/src/graph/feature/proptest_helpers.rs