dynamic inherits class

meta_test

#!/usr/bin/env python
# -*- coding: utf-8 -*-

class A(object):
    def __init__(self):
        print 'A init'
    
    @classmethod
    def foo(cls):
        print 'A foo'

    def bar(self):
        print 'A bar'

class B(object):
    def __init__(self):
        print 'B init'
    
    @classmethod
    def foo(cls):
        print 'B foo'

    def bar(self):
        print 'B bar'

import random        
def get_random_key():
    return random.choice(['A', 'B'])

class AttrType(type):
    def __new__(meta, name, bases, dct):
        klass_key = get_random_key()
        klass = None
        if klass_key == 'A':
            klass = A
        elif klass_key == 'B':
            klass = B
            
        bases = list(bases)
        bases.insert(0, klass)
        bases = tuple(bases)
        
        return super(AttrType, meta).__new__(meta, name, bases, dct)

class MyClass(object):
    __metaclass__ = AttrType
        
if __name__ == '__main__':
    MyClass.foo()

    obj = MyClass()
    obj.bar()

    obj = MyClass()
    obj.bar()