How to correctly specify the type of the argument?

November 11, 2022

I have a ButtonTypes class:

class ButtonTypes:
    def __init__(self):
        self.textType = "text"
        self.callbackType = "callback"
        self.locationType = "location"
        self.someAnotherType = "someAnotherType"

And a function that should take one of the attributes of the ButtonTypes class as an argument:

def create_button(button_type):
    pass

How can I specify that the argument of the create_button function should not just be a string, but exactly one of the attributes of the ButtonTypes class?

Something like this:
def create_button(button_type: ButtonTypes.Type)

As far as I understand, I need to create a Type class inside the ButtonTypes class, and then many other classes for each type that inherit the Type class, but I think something in my train of thought is wrong.

>Solution :

It sounds like you actually want an Enum:

from enum import Enum

class ButtonTypes(Enum):
    textType = "text"
    callbackType = "callback"
    locationType = "location"
    someAnotherType = "someAnotherType"

def func(button_type: ButtonTypes):
    # Use button_type

The enum specifies a closed set of options that the variable must be a part of.