Creating and Implementing an interface using Python?

I have two (2) questions: Firstly, how do I create the FlyBehavior interface using Python? Secondly, how do I implement the FlyBehavior interface in the FlyWithWings class, using Python (see below)? I'm learning Design Patterns by Head First and I want to rewrite the following Java classes using Python

public abstract class Duck {

    // Reference variables for the 
    // behavior interface types
    FlyBehavior flyBehavior;
    QuackBehavior quackBehavior;

    public Duck() {
    }

    // Delegate to the behavior class
    public void performFly(){
        flyBehavior.fly();
    }

    // Delegate to the behavior class
    public void performQuack(){
        quackBehavior.quack();
    }
}

Here is the interface that all flying behavior classes implement

public interface FlyBehavior {
    public void fly();
}

Here is the flying behavior implementation for ducks that do fly

public class FlyWithWings implements FlyBehavior {
    public void fly(){
    System.out.println("I'm flying");
    }
}

Here is what I have so far using Python. Below is my Python abstract Duck class

import abc

class Duck:
    __metaclass__=abc.ABCMeta


    FlyBehavior FlyBehavior;
    QuackBehavior QuackBehavior;

    @abc.abstractmethod
    def __init__():
        return

    @abc.abstractmethod
    def performFly():
        return

    @abc.abstractmethod
    def performQuack():
        return

Here is where I'm stuck trying to create the interface, and trying to implement the interface.