@NotNull
  public static List<PyDebugValue> parseReferrers(final String text, final PyFrameAccessor frameAccessor) throws PyDebuggerException {
    final List<PyDebugValue> values = new LinkedList<>();

    final XppReader reader = openReader(text, false);

    while (reader.hasMoreChildren()) {
      reader.moveDown();
      if (reader.getNodeName().equals("var")) {
        PyDebugValue value = parseValue(reader, frameAccessor);
        value.setId(readString(reader, "id", null));
        values.add(value);
      }
      else if (reader.getNodeName().equals("for")) {
        //TODO
      }
      else {
        throw new PyDebuggerException("Expected <var> or <for>, found " + reader.getNodeName());
      }
      reader.moveUp();
    }

    return values;
  }
@NotNull
  public static List<PyDebugValue> parseReferrers(final String text, final PyFrameAccessor frameAccessor)