private void buildSubClassesMapImpl(PyClass aClass, HashSet<PyClass> visited) {
    visited.add(aClass);
    for (PyClass clazz : aClass.getSuperClasses(null)) {
      getSubclasses(clazz).add(aClass);
      if (!visited.contains(clazz)) {
        buildSubClassesMapImpl(clazz, visited);
      }
    }
  }
private void buildSubClassesMapImpl(PyClass aClass, HashSet<PyClass> visited)