public static Element createRuleElement(Document document, LSystem lsystem,
			String left) {
		Element re = createElement(document, RULE_NAME, null, null);
		re.appendChild(createElement(document, RULE_LEFT_NAME, null, left));
		List[] replacements = lsystem.getReplacements(left);
		for (int i = 0; i < replacements.length; i++) {
			re.appendChild(createElement(document, RULE_RIGHT_NAME, null,
					listAsString(replacements[i])));
		}
		return re;
	}