python 类和__class__理解

__class__可理解为对象所属的父类

class A:
    def __init__(self,url):
        self.url = url
    def out(self):
        return self.url

a = A('news.163.com')
print a.out()

b = a.__class__('www.bccn.net')
print b.out()

print A
print a.__class__

　　a.__class__等价于A

元类的理解，

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