Python----面向对象---练习一：在元类中控制把自定义类的数据属性都变成大写

在元类中控制把自定义类的数据属性都变成大写

class Mymeta(type):
    def __new__(cls, class_name, class_bases, class_dic):
        print(cls)
        print(class_name)
        print(class_bases)
        print(class_dic)
        update_attrs = {}
        for k, v in class_dic.items():
            if not callable(v) and not k.startswith('__'):
                update_attrs[k.upper()] = v
            else:
                update_attrs[k] = v
        print(update_attrs)
        return type.__new__(cls, class_name, class_bases, update_attrs)


class Chinese(object, metaclass=Mymeta):
    '''
    xxx
    '''

    country = 'China'
    tag = '123'

    def __init__(self, name, age):
        self.name = name
        self.age = age

    def talk(self):
        print('%s is talking' % self.name)

print(Chinese.__dict__)

结果为：

<class '__main__.Mymeta'>
Chinese
(<class 'object'>,)
{'__module__': '__main__', '__qualname__': 'Chinese', '__doc__': '
    xxx
    ', 'country': 'China', 'tag': '123', '__init__': <function Chinese.__init__ at 0x00000236B593B620>, 'talk': <function Chinese.talk at 0x00000236B593B6A8>}
{'__module__': '__main__', '__qualname__': 'Chinese', '__doc__': '
    xxx
    ', 'COUNTRY': 'China', 'TAG': '123', '__init__': <function Chinese.__init__ at 0x00000236B593B620>, 'talk': <function Chinese.talk at 0x00000236B593B6A8>}
{'__module__': '__main__', '__doc__': '
    xxx
    ', 'COUNTRY': 'China', 'TAG': '123', '__init__': <function Chinese.__init__ at 0x00000236B593B620>, 'talk': <function Chinese.talk at 0x00000236B593B6A8>, '__dict__': <attribute '__dict__' of 'Chinese' objects>, '__weakref__': <attribute '__weakref__' of 'Chinese' objects>}

找到数据属性，然后对数据属性进行操作，