In Python, a decorator is a design pattern that allows you to add new functionality to an existing object, such as a function or a class, without modifying its structure. Decorators are implemented as functions that take another function as an argument and return a modified version of it. They are a powerful and useful tool in Python, enabling programmers to easily modify the behavior of functions and classes.
To understand decorators, its important to grasp some key concepts:
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First-class objects: In Python, functions are first-class objects, which means they can be used or passed as arguments. This property allows decorators to take functions as input.
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Nested functions: Python supports nested functions, where one function is defined inside another. Decorators often use this feature to define an inner function that adds the desired functionality to the original function.
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Callable objects: Any object that implements the special
__call__()method is considered callable. Decorators, being functions that return functions, are callable objects.
Here's a simple example of a decorator that adds a timer to a function:...
