new-style classes defined in the type and class unification effort in python (introduced without breaking backwards compatibilitysimplermore regular and more powerful it will be the default (and uniquein the future documents built-in types ( dictcan be subclassed propertiesattributes managed by get/set methods static and class methods (via descriptor apicooperative classes (sane multiple inheritancemeta-class programming unifying types and classes in python pep- making types look more like classes pep- subtyping built-in types