1

def upper_attr(class_name, class_parents, class_attr):    """    返回一个对象,将属性都改为大写的形式    """    attrs = ((name, value) for name, value in class_attr.items() if not name.startswith('__'))    uppercase_attrs = dict((name.upper(), value) for name, value in attrs)    return type(class_name, class_parents, uppercase_attrs)# 一种方式： 使用函数赋值给metaclass__metaclass__ = upper_attrpw = upper_attr('Trick', (), {
   'bar': 0})print hasattr(pw, 'bar')print hasattr(pw, 'BAR')print pw.BAR# ==============================================================# 另一种方式： 使用赋值给metaclassclass UpperAttrMetaClass(type):    def __new__(mcs, class_name, class_parents, class_attr):        attrs = ((name, value) for name, value in class_attr.items() if not name.startswith('__'))        uppercase_attrs = dict((name.upper(), value) for name, value in attrs)        return super(UpperAttrMetaClass, mcs).__new__(mcs, class_name, class_parents, uppercase_attrs)class Trick(object):    __metaclass__ = UpperAttrMetaClass    bar = 12    money = 'unlimited'print Trick.BARprint Trick.MONEY

 参考: http://blog.jobbole.com/21351/   http://python.jobbole.com/85126/