code: T tz(TimeZone defaultTimeZone, boolean outlookCompatible) {
  		this.defaultTimeZone = (defaultTimeZone == null) ? null : TimezoneAssignment.download(defaultTimeZone, outlookCompatible);
  		return this_;
  	}
docs: <p>
  Sets the timezone to use when outputting date values (defaults to UTC).
  </p>
  <p>
  This method downloads an appropriate VTIMEZONE component from the <a
  href="http://www.tzurl.org">tzurl.org</a> website.
  </p>
  @param defaultTimeZone the default timezone or null for UTC
  @param outlookCompatible true to download a VTIMEZONE component that is
  tailored for Microsoft Outlook email clients, false to download a
  standards-based one
  @return this
  @throws IllegalArgumentException if an appropriate VTIMEZONE component
  cannot be found on the website