How to use the phovea_core/src/ajax.getAPIJSON function in phovea_core

export function listNamedSets(idType : IDType | string = null):Promise {
  const args = idType ? { idType : resolve(idType).id} : {};
  return getAPIJSON('/targid/storage/namedsets/', args).then((sets: IStoredNamedSet[]) => {
    // default value
    sets.forEach((s) => s.type = s.type || ENamedSetType.NAMEDSET);

    sets = sets.filter((d) => d.creator === retrieve('username'));
    return sets;
  });
}

private static getJSONRatio2D(pair) {
    const operations = ChangeTypes.forURL();
    return ajax.getAPIJSON(`/taco/compare/${pair[0]}/${pair[1]}/${operations}/ratio_2d`);
  }

private static getJSON(pair) {
    const operations = ChangeTypes.forURL();
    return ajax.getAPIJSON(`/taco/compare/${pair[0]}/${pair[1]}/${operations}/bar_chart`);
  }

private static getJSON(pair): Promise {
    const operations = ChangeTypes.forURL();
    return ajax.getAPIJSON(`/taco/compare/${pair[0]}/${pair[1]}/${operations}/bar_chart`);
  }

private static getJSONHistogram(pair, binRows, binCols) {
    const operations = ChangeTypes.forURL();
    return ajax.getAPIJSON(`/taco/compare/${pair[0]}/${pair[1]}/${binRows}/${binCols}/${operations}/histogram`);
  }

private static getJSON(pair) {
    const operations = ChangeTypes.forURL();
    return ajax.getAPIJSON(`/taco/compare/${pair[0]}/${pair[1]}/${operations}/diff_heat_map`);
  }