Have you dealt with the use of descriptors in your projects?

In Python, descriptors are objects that manage access to attributes of other objects through the methods __get__, __set__, and __delete__. They are often used to implement properties, data validation, or lazy evaluation.

Example of a simple descriptor for controlling access to an attribute:

class PositiveNumber:
    def __get__(self, instance, owner):
        return instance._value

    def __set__(self, instance, value):
        if value < 0:
            raise ValueError("Value must be positive")
        instance._value = value

class MyClass:
    number = PositiveNumber()

obj = MyClass()
obj.number = 10  # works
obj.number = -5  # raises ValueError

Using descriptors helps centralize the logic for attribute access and validation.