code: public void writeXml(File file) throws TransformerException, IOException {
  		Biweekly.writeXml(this).indent(2).go(file);
  	}
docs: <p>
  Marshals this iCalendar object to its XML representation (xCal).
  </p>
  <p>
  If this iCalendar object contains user-defined property or component
  objects, you must use the {@link Biweekly}, {@link XCalWriter}, or
  {@link XCalDocument} classes instead in order to register the scribe
  classes.
  </p>
  @param file the file to write to
  @throws IllegalArgumentException if this iCalendar object contains
  user-defined property or component objects
  @throws TransformerException if there's a problem writing to the file
  @throws IOException if there's a problem opening the file