def get_Xy(dat):
    """
    Splits a structured df (generated by a single_CV_fold object) to X,y
    """
    X_s = dat.drop(columns=["ind", "target"])
    feats = X_s.columns.tolist()

    X_s = X_s.values
    y_s = dat['target'].values
    return X_s, y_s, feats