__init__.py 文件源码

def is_class_sealed(klass):
    """
    Returns a boolean indicating whether or not the supplied class can accept
    dynamic properties.

    @rtype: C{bool}
    @since: 0.5
    """
    mro = inspect.getmro(klass)
    new = False

    if mro[-1] is object:
        mro = mro[:-1]
        new = True

    for kls in mro:
        if new and '__dict__' in kls.__dict__:
            return False

        if not hasattr(kls, '__slots__'):
            return False

    return True