In this tutorial, we'll show the reader how they can use decorators in their Python functions. Decorator Design Pattern in Python Back to Decorator description """ Attach additional responsibilities to an object dynamically. In this tutorial, you will learn how you can create a decorator and why you should use it. In Python, functions are first-class objects, so they can be passed into and out of functions just like any other variable. Decorators provide a flexible alternative to subclassing for extending functionality. """ First, you need to understand that the word “decorator” was used with some trepidation in Python, because there was concern that it would be completely confused with the Decorator pattern from the Design Patterns book.At one point other terms were considered for the feature, but “decorator” seems to be the one that sticks. A function registration decorator that takes no arguments has the following structure: The Decorator Design Pattern gives us a method to add new functionality to an object, dynamically. This supports more readable applications of the DecoratorPattern but also other uses as well. Python makes implementing this pattern relatively easier as compared to other languages, due to its builtin feature called decorators. The decorator design pattern provides a way to modify a function, often by adding functionality before and after it runs. Decorators vs. the Decorator Pattern¶. Put simply: decorators wrap a function, modifying its behavior. This is ideal when … A Python decorator is a specific change to the Python syntax that allows us to more conveniently alter functions and methods (and possibly classes in a future version). One of my favorites is decorators. In the context of design patterns, decorators dynamically alter the functionality of a function, method or class without having to directly use subclasses. @THC4K: The decorator pattern (as opposed to python decorators) is used to add behavior to an object at runtime. This pattern is very common in Python applications, as it allows two or more subsystems to communicate without knowing much about each other, what is formally known as a "decoupled" design. However, wrapper() has a reference to the original say_whee() as func, and calls that function between the two calls to print(). Decorators in Python. Before moving on, let’s have a look at a second example. Decorator pattern allows a user to add new functionality to an existing object without altering its structure. – Björn Pollex Jun 26 '10 at 11:13 This type of design pattern comes under structural pattern as this pattern acts as a wrapper to existing class. The decorator pattern is a design pattern used in statically typed object-oriented programming languages to allow functionality to be added to objects at run time; Python decorators add functionality to functions and methods at definition time, and thus are a higher-level construct than decorator-pattern classes. Python has an interesting feature called decorators to add functionality to an existing code. I wanted to find the way to this in Python. A decorator is a design pattern in Python that allows a user to add new functionality to an existing object without modifying its structure. Because wrapper() is a regular Python function, the way a decorator modifies a function can change dynamically. Python Decorators A decorator takes in a function, adds some functionality and returns it. import abc class Component(metaclass=abc.ABCMeta): """ Define the interface for objects that can have responsibilities added to them dynamically. 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