core.py 文件源码

def __new__(mcs, name, bases, attrs):
        # We can't use it on __init__ because
        # cached_property fires on property's __get__
        for attr in mcs.CACHED_ATTRS:
            if attr in attrs:
                attrs[attr] = cached_property(attrs[attr])
        return super(WidgetMeta, mcs).__new__(mcs, name, bases, attrs)