class Application(object):

    def __init__(self):
        print('init application')
        self.do_init()

    def do_init(self):
        print('1. app')


class SecondApp(Application):

    def do_init(self):
        super().do_init()
        print('2. SecondApp')


class ThirdApp(Application):

    def do_init(self):
        super().do_init()
        print('3. ThirdApp')


class FourApp(ThirdApp):

    def do_init(self):
        super().do_init()
        print('4. FourApp')


class FiveApp(ThirdApp):

    def do_init(self):
        super().do_init()
        print('5. FiveApp')


class FinApp(SecondApp, FourApp, FiveApp):

    def do_init(self):
        super().do_init()
        print('FinApp')

testing = FinApp()