docs: public static PeriodFormatter alternateExtendedWithWeeks() {
          if (cAlternateExtendedWihWeeks == null) {
              cAlternateExtendedWihWeeks = new PeriodFormatterBuilder()
                  .appendLiteral("P")
                  .printZeroAlways()
                  .minimumPrintedDigits(4)
                  .appendYears()
                  .appendSeparator("-")
                  .minimumPrintedDigits(2)
                  .appendPrefix("W")
                  .appendWeeks()
                  .appendSeparator("-")
                  .appendDays()
                  .appendSeparatorIfFieldsAfter("T")
                  .appendHours()
                  .appendSeparator(":")
                  .appendMinutes()
                  .appendSeparator(":")
                  .appendSecondsWithOptionalMillis()
                  .toFormatter();
          }
          return cAlternateExtendedWihWeeks;
      }