How to Use Properties in Python

Python provides a more elegant and convenient way to define getters and setters using the property function.

This function allows you to define a property that is used like an attribute, but with the ability to control its access and modification.

Properties make access to attributes feel more natural, and their syntax is cleaner and easier to understand.

Defining Properties

The property function is used to define a property. You can optionally pass a getter, a setter, and a deleter to this function.

class Person:
    def __init__(self, name, age):
        self._name = name
        self._age = age

    @property
    def name(self):
        return self._name

    @name.setter
    def name(self, name):
        if isinstance(name, str):
            self._name = name
        else:
            raise ValueError("Name must be a string")
    
    @property
    def age(self):
        return self._age

    @age.setter
    def age(self, age):
        if isinstance(age, int) and age > 0:
            self._age = age
        else:
            raise ValueError("Age must be a positive integer")

Using Properties

With the properties defined, you can get and set values using attribute syntax, making the code cleaner and more readable.

For example,

person = Person("John", 25)
print(person.name)  # Output: John
person.name = "Carlos"
print(person.name)  # Output: Carlos

print(person.age)  # Output: 25
person.age = 30
print(person.age)  # Output: 30

Notice that I don’t have to invoke a setter or getter method. I simply get the value with ., and set it with =, just like it were an attribute.