How to call grandparent's `__str__` from child class in python?

Suppose we have 3 classes grandparent,parent and child where parent inherits from grandparent and child inherits from parent. I want to call the __str__ of grandparent in class child. How can I do it?

class grandparent:
    def __init__(self):
        pass
    def __str__(self):
        return f'grandparent'

class parent(grandparent):
    def __init__(self):
        pass
    def __str__(self):
        return f'{super().__str__()},parent'

    
class child(parent):
    def __init__(self):
        pass
    def __str__(self):
        return f'{super().__str__()},child'

In this case if I make an object from child class, after printing it I see :

c = child()
print(c) # prints 'grandparent,parent,child'

I want to see 'grandparent,child' by calling the grandparent’s __str__ in child class.

>Solution :

There are several ways how to achieve this.

First is to pass parent class to super method:

class child(parent):
    def __init__(self):
        pass

    def __str__(self):
        return f'{super(parent, self).__str__()},child'

In that case we don’t need to know "grandparent" class name. In case if you know the name of "grantparent" class we could use direct class name:

class child(parent):
    def __init__(self):
        pass

    def __str__(self):
        return f'{grandparent.__str__(self)},child'

Those 2 methods is the best practice, any of other approaches does not so flexible.