How Do Python Descriptors\' `__get__` and `__set__` Methods Control Property Behavior?

Understanding Python Descriptors: get and set

Python descriptors allow developers to create custom property behavior by implementing specific methods, such as get and __set__. These methods serve as a means to control the behavior of properties defined within a class.

Descriptor Use

In the provided example, the Celsius class acts as a descriptor and is added to the Temperature class. By accessing the celsius property of the Temperature instance, the get method of the Celsius descriptor is invoked. This returned value is the value stored within the descriptor itself.

Parameters

The get method takes three parameters: self, instance, and owner. Self simply refers to the descriptor itself, while instance is the instance of the class that the descriptor is attached to. Owner is the class that defines the property to which the descriptor is attached.

Purpose

Descriptors are useful for encapsulating custom behavior that is associated with properties. For example, they can serve as a way to cache expensive operations or perform validation procedures when a property is set. This level of customization allows for greater control over property behavior and opens up possibilities for complex operations.

Example Usage

In the provided example, creating an instance of the Temperature class and accessing the celsius property will invoke the get method of the Celsius descriptor. This method then returns the value stored within the descriptor.

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