code: public static Currency getInstance(ULocale locale) {
          String currency = locale.getKeywordValue("currency");
          if (currency != null) {
              return getInstance(currency);
          }
  
          if (shim == null) {
              return createCurrency(locale);
          }
  
          return shim.createInstance(locale);
      }
docs: Returns a currency object for the default currency in the given
  locale.