A Python descriptor

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A Python descriptor is an object attribute with “binding behavior,” meaning its attribute access has been overridden by methods in the descriptor protocol. These methods are __get__, __set__, and __delete__. If any of these methods are defined for an object, it can be considered a descriptor. Descriptors are used to manage the attributes of different classes using the same code or to create attributes that can only be accessed through special methods.

Example: Creating and Using a Descriptor

Let’s create a simple descriptor that sets and gets a value, ensuring the value is always an integer.

class IntegerDescriptor:
    def __init__(self):
        self.value = 0

    def __get__(self, instance, owner):
        return self.value

    def __set__(self, instance, value):
        if not isinstance(value, int):
            raise TypeError("Value must be an integer")
        self.value = value

class MyClass:
    number = IntegerDescriptor()

# Using the descriptor
my_instance = MyClass()
my_instance.number = 10  # Works fine
print(my_instance.number)  # Output: 10

try:
    my_instance.number = "Hello"  # Raises TypeError
except TypeError as e:
    print(e)  # Output: Value must be an integer

In this example:

• IntegerDescriptor defines __get__ and __set__ methods to control access to the…