python __init__ method in inherited class

Question

I would like to give a daughter class some extra attributes without having to explicitly call a new method. So is there a way of giving the inherited class an __init__ type method which does not override the __init__ method of the parent class?

I have written the code below purely to illustrate my question (hence the poor naming of attributes etc).

class initialclass():

    def __init__(self):

        self.attr1 = 'one'

        self.attr2 = 'two'    

class inheritedclass(initialclass):

    def __new__(self):

        self.attr3 = 'three'

    def somemethod(self):

        print 'the method'

a = inheritedclass()

for each in a.__dict__:

    print each

#I would like the output to be:

attr1

attr2

attr3

Thank you

Answer 1

As far as I know that's not possible, however you can call the init method of the superclass, like this:

class inheritedclass(initialclass):

    def __init__(self):

        initialclass.__init__(self)

        self.attr3 = 'three'