Inheritance private attributes

[Larz60+]

class Primary():
    def __init__(self, param1, param2):
        self.param1 = param1
        self.__param2 = param2

    def getP1(self):
        return self.param1

    def getP2(self):
        return self.__param2

class Secondary(Primary):
    def __init__(self, param1, param2, param3):
        Primary.__init__(self, param1, param2)
        self.__param3 = param3

    def getP3(self):
        return self.__param3

    def test(self):
        print (self.getP2())

#Main

p = Primary('a', 'b')
s = Secondary('a', 'b', 'c')

s.test()