def METHOD_NAME():
    knn = KNeighborsClassifier()
    sfs = SFS(
        estimator=knn,
        k_features=(3, 4),
        forward=True,
        floating=True,
        fixed_features=(0, 1),
        verbose=0,
    )
    sfs.fit(X_iris, y_iris)
    for k in sfs.subsets_:
        assert 0 in sfs.subsets_[k]["feature_idx"]
        assert 1 in sfs.subsets_[k]["feature_idx"]