Somewhere in the pipeline, the metadata of the references and probes (age, gender, ...) are lost. They are no longer available in the score files. Issue encountered with `bob bio pipeline simple mobio-all arcface-insightface`. After a first investigation: - The metadata attributes are present when creating the `Sample` objects with the `Database`. - The `ScoreWriter` receives `Sample` objects that are already missing those attributes. - The `Distance` BioAlgorithm seems to transform samples into bags. Maybe more investigation needed here.