Howdy Pardner

Enums (enumerations) be a way to define a data type that can only hold a limited set o’ pre-defined values. This makes it easier to avoid mistakes by makin’ sure a variable can only have valid values.

Enums ain’t strictly used for validation, but they help us limit which values be valid for a variable, and thus they can help prevent errors.

Fer example, if ya got a class that represents a car, ya can use an Enum to define what colors the car can be:

from enum import Enum

class CarColor(Enum):
    RED = "red"
    BLUE = "blue"
    GREEN = "green"
    BLACK = "black"
    WHITE = "white"

class Car:
    def __init__(self, make: str, model: str, year: int, color: CarColor):
        self.make = make
        self.model = model
        self.year = year
        self.color = color

Why?

Our IDE gives better autocompletion when we use enums, and we avoid (make it difficult) settin’ invalid values. If we try to assign a color that ain’t defined in CarColor, Python’ll throw an error. This makes the code more robust and easier to maintain. The fewer possible errors that can happen, the better quality we get in the code.

Now, picture this: we got a function that handles payment methods: PayPal, VISA, MASTERCARD and BITCOIN. By usin’ an Enum for payment methods, we can make sure the function only receives valid payment methods, and not "MASTERCARDD" or "CASH", which can lead to errors in the program.

Task 1 - Make a Enum

Make a Enum called EyeColor and implement this in the Person class from the previous module. EyeColor should have the following values:

• BLUE
• BROWN
• GREEN
• HAZEL