How to access class variable? instances vs class

[Gribouillis]

At first sight, there is no difference: if it doesn't find the raise_amount member in the instance, Python will look for the member in the class, then in the ancester classes if any.

The self.raise_amount is the most robust syntax if you decide to change the structure of the classes later. For example if you change the name of the Employee class, you won't need to change self.raise_amount. Things get even better when you start defining subclasses, for example

class SpecialEmployee(Employee):
    raise_amount = 1.10

jane = SpecialEmployee('Jane', 'Doe', 5000)
jane.apply_raise()

Then Jane's new pay will be 5500 because self.raise_amount will use Jane's class instead of the Employee class.