#100DaysOfCode in Python Transcripts
Chapter: Appendix: Python language concepts
Lecture: Concept: Classes
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Classes and object-oriented programming are very important parts of modern programming languages and in Python, they play a key role.
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Here we are creating a class that we can use in some kind of game or something that works with creatures.
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So to create a creature class, you start with the keyword class, and then you name the type and you say colon and everything indented into that block
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or that code suite to do with the class is a member of the class. Most classes need some kind of initialization to get them started,
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that's why you create a class, we want them to start up all ready to go and bundled up with their data and then combine that with their methods,
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their behaviors and they make powerful building blocks in programming. So most classes will have an initializer,
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and the initializer is where you create the variables and validate
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that the class is getting setup in correct way, for example making sure the name is not empty,
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the level is greater than zero, but less than a 100, something like that. Now this is often refered to as __init__ sometimes just init,
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or even a constructor and these dunder methods because they have double underscores at the beginning and at the end,
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they are part of the Python data model which lets us control many things about classes,
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so you'll see a lot of methods like this but the __init__ method is probably the most common on classes.
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If you want to create behaviors with your class, and if you have a class that's almost certainly part of what you are going to do,
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you are going to define methods just like functions that are standalone, methods or functions that are parts of classes
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and you define them in exactly the same way, the only difference is typically they take a self parameter,
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the self parameter is passed explicitly everywhere when you are defining the class,
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some languages have a "this" pointer, that's sort of implicit but in Python,
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we call this self and it refers to the particular instance of the creature that exists,
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you might have many creatures but the self is the one that you are working with currently. So just be aware you have to pass that explicitly everywhere
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unless you have what is called a class method or a static method.