Polymorphism in Python Question

[Oliver]

Coming from Java, I'm wondering how in Python you "program to interface, not to implementation", when Python doesn't have, well, interfaces?

For example, in Java, you could create a class hierarchy like Animal->Dog. Then, in code, you could create an object like this (pseud ocode):

Class Animal

Class Dog extends Animal
.
.
.
Animal animal = new Dog(); // polymorphism in Java
animal.makeSound();

Here, the variable dog has an Animal "type", but is an instance of a Dog class.

---

In Python, can you do the same type of thing?

class Animal():
def sound(self):
print("Basic Animal")

class Dog(Animal):
def sound(self):
print("Woof woof!")

===

How would you complete this code so it's polymorphic (using the Animal class to reference the dog class as in the Java example above)?

Thanks,