Intro to Python - Day 4 - Modifying a Class Variable from Within the Class Itself

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Today in one of the lessons I worked on for the fantastic backend development tutorial boot.dev for one lesson we were asked to modify a class variable from within a method.

This follows on closely to yesterday's blog post about classes and object oriented programming in Python.

It actually took me a bit of digging and eventually I just had to break down and ask ChatGPT to find the answer. Most of the documentation and blog posts out there only discuss changing a class variable from outside of the variable.

The answer is, to modify a class variable from within the class itself, you must use the name of the class itself.

For example, if I have a class called Company and a class variable on it called number_of_employees = 0. Say I have a method called hire_new_employee that takes in their name and position title, but also increments number_of_employees by 1:

class Company:
    number_of_employees = 0

    def __init__(self, company_name):
        self.company_name = company_name

    def hire_new_employee(self, name, position):
        self.name = name
        self.position = position
        Company.number_of_employees += 1

As I show, you need to call the class itself and set the variable on it from within the class method, or wherever you are modifying the variable.

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