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Python init and self what do they do?

Can anyone explain what __init__(self) does? I’ve been reading other questions and people mentioning super classes? What’s a super class? I thought procedures were supposed to start off with

def print_word(word):
    print word

Is __init__(self) some sort of special case since it has underscores and “self”? sorry for the lack of specific terminology… still learning.

Answer 1

__init__(self) is a special function used within what are called “classes”. Classes let you define your own datatypes/object and this __init__ function is called when ever you create a new instance of the datatype/object that you’ve defined. It’s like saying “hey, every time you make one of these things, make sure you run this code too”. In object oriented programming, we call this kind of function a “constructor”. It’s a function that’s used to “construct” a new object. The self is a reference to the object that’s actually being created. In other words, the object is technically already created by the time you get to your __init__ function. __init__ just gives you the opportunity to initializes various aspects of your object (hence the name __init__).

Python is a mixture of both functional, procedural, and object oriented paradigms. This __init__ business has to do with objects. For more information on object oriented programming you can checkout the wikipedia article.