code: public List<ParsedNode> getChildren(String namespace, String nodename) {
          List<ParsedNode> returnList = new ArrayList<>();
          for (ParsedNode node : children) {
              if (nodeMatches(node, namespace, nodename)) {
                  returnList.add(node);
              }
          }
          return Collections.unmodifiableList(returnList);
      }
docs: Returns all child nodes with the given namespace and name.
  If none match, an empty list is returned.
  Returned list is unmodifiableList.