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Python is fundamentally an object-oriented language.

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In fact, in Python 3 everything is an object.

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So let's look at how we can create our own objects.

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We'll start by making a working copy of syntax.py. I'll call this syntax-objects.py.

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And we'll open our working copy.

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Now we'll go into a lot more detail on objects later on.

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The point here is just to get a handle on the syntax of creating objects.

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So we'll go ahead and start by defining a class.

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Now a class is the definition that's used when creating an object in Python.

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So we'll use the class keyword, and we'll call this class Egg.

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And the first thing we'll define inside of the class is a constructor.

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And a constructor in Python is a method, or a function inside the class, and has a

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special name which is __init__, like that.

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And all methods within classes have self as the first argument.

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This is a reference to the object itself.

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And it's traditionally called self.

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It's not required, but it's a really, really good idea to always call it self.

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And following self can be arguments that can be used in constructing the object.

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And in this case we are going to say how do you want your eggs?

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And so it'll be a kind of eggs, and we'll call it kind, and we'll give it a

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default value of fried.

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And then we will assign this value to an object variable.

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And object variables are referenced to the object itself, so we'll say self.kind

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= kind, and that will create an object variable that will be carried around and

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encapsulated in the object.

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And so each instance of this class, each object, can have a different value for kind.

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Now let's define a method for finding out what kind.

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And we'll call this whatKind, and it has self as the only argument.

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And we'll simply return self.kind.

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Now we have a class.

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It's a very simple class, and it doesn't do anything terribly useful, but it's

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good as an example of the syntax of how you create a class.

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And now we'll go ahead and create an object.

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Now an object is an instance of a class.

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You can think of the class as like the blueprint.

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This defines how the object is created, and the object itself is an instance.

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The object is an encapsulation of all of the methods and the variables that are

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inside of the class.

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And so we'll say fried = Egg, like that.

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And that will create a object called fried, based on the class, Egg.

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And you notice we don't have anything in the parentheses, so it will use this

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default value when it creates or constructs the object.

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The constructor is called every time you create an object.

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So here we've created an object with the assignment operator.

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And so the first thing it'll do is it'll call this Constructor, and it'll

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assign this default value.

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We can also create a scrambled egg, like this.

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And so when we print these out, later on we can say print(fried.whatKind()).

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And if we save this and run it, it says that it's a fried egg.

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Instead of the fried kind, I used the scrambled kind, and this is just this different

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object, but it's using exactly the same interface.

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If I save it and run it,

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now we have a scrambled egg.

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So this is just a very simple and a very simplistic example of how an object is created.

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We have a definition, which is called a class, and this defines the blueprint of

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how these objects are made.

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And then we have a couple of objects that are created using that class.

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And so these are considered instances of that class, or objects.

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And these objects are completely functional, and they contain data, and they

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contain code in the form of these methods, and that is how you define and

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create objects in Python.