Getter and setter methods in Python - Mini Project: Build & Apply

Using Getter and Setter Methods in Python

📖 Scenario: You are creating a simple program to manage a person's age. You want to control how the age is accessed and changed to keep it valid.

🎯 Goal: Build a Python class called Person that uses getter and setter methods to safely access and update the age attribute.

📋 What You'll Learn

Create a class named Person with a private attribute _age.

Add a getter method called get_age to return the current age.

Add a setter method called set_age to update the age only if the new value is between 0 and 120.

Create an instance of Person and set the age using the setter.

Print the age using the getter.

💡 Why This Matters

🌍 Real World

Getter and setter methods are used in many programs to protect important data and make sure it stays correct.

💼 Career

Understanding how to control access to data is important for writing safe and reliable software, a key skill for any programmer.

1

Create the Person class with a private age attribute

Create a class called Person with an __init__ method that sets a private attribute _age to 0.

Python

class Person:
    def __init__(self):
        # Your code here

Need a hint?

Use self._age = 0 inside the __init__ method to create the private attribute.

2

Add getter and setter methods for age

Add a method called get_age that returns self._age. Add another method called set_age that takes a parameter new_age and sets self._age to new_age only if it is between 0 and 120.

Python

class Person:
    def __init__(self):
        self._age = 0

    # Your code here

Need a hint?

The getter returns self._age. The setter checks if new_age is between 0 and 120 before setting self._age.

3

Create a Person instance and set the age

Create an instance of Person called person. Use the set_age method to set the age to 25.

Python

class Person:
    def __init__(self):
        self._age = 0

    def get_age(self):
        return self._age

    def set_age(self, new_age):
        if 0 <= new_age <= 120:
            self._age = new_age

# Your code here

Need a hint?

Create the object with person = Person() and set age with person.set_age(25).

4

Print the age using the getter method

Use print to display the age by calling person.get_age().

Python

class Person:
    def __init__(self):
        self._age = 0

    def get_age(self):
        return self._age

    def set_age(self, new_age):
        if 0 <= new_age <= 120:
            self._age = new_age

person = Person()
person.set_age(25)

# Your code here

Need a hint?

Use print(person.get_age()) to show the age.