pub fn decode(
  preprocessor: ZList(Attribute),
  encoded_datapoint: ZList(Float),
) -> Map(String, String)

pub fn encode(
  preprocessor: ZList(Attribute),
  datapoint: Map(String, String),
) -> ZList(Float)

pub fn init(
  keys_with_flags: ZList(tuple(String, Bool)),
  dataset: ZList(Map(String, String)),
) -> ZList(Attribute)

pub fn of_json(s: String) -> ZList(Attribute)

pub fn to_json(preprocessor: ZList(Attribute)) -> String