How to use the cldr.extractLanguageSupplementalMetadata function in cldr

const extractLanguageDataForLocale = locale => {
  // Get the list of all languages.
  const languages = cldr.extractLanguageSupplementalData(locale);
  // Get the list of all remaining languages.
  const oldLanguages = cldr.extractLanguageSupplementalMetadata(locale);
  // Get the list of all language names
  const languageNames = cldr.extractLanguageDisplayNames(locale);

  /* Here we are filtering the oldLanguages for having only the ones that
   * are not deprecated and has a key or its replacement key with length of 2
   * as stipulated by the ISO 639 (1, 2)
   *
   * Let's say that we got this coming from cldr
   *  {
   *    bh: { replacement: 'bhr', reason: 'legacy'},
   *    tr: { replacement: 'thr', reason: 'deprecated'},
   *    mar: { replacement: 'ma', reason: 'legacy'},
   *    adr: { replacement: 'adr-a', reason: 'legacy'},
   *  }
   *
   * The output with the following function would be: