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Welcome back. So, in this piece of code.

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Here we set the instance variable for x for both point one and point two on lines 89.

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Now, even though you can do this in your pipeline code,

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this isn't the way that you should set instance variables.

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So, instead you should set instance variables in what's called a constructor.

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Now, a constructor is a special method that's meant to

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initialize Python instances, including instance variables.

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So, the constructor is named what's called

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underscore underscore init underscore underscore.

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It's just a special method with this name

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underscore underscore init underscore underscore.

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Now, I'm going to call this instead

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of underscore underscore I'm going to say dunderscore.

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So, that we'd make this dunderscore init dunderscore.

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But instead of saying dunderscore init dunderscore.

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I'm just going to say dunderscore init for now.

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So, we want to define our constructor dunderscore init.

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So, the way that we do that is we define this method and we can say def

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dunderscore init dunderscore and init

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just like every other method takes in self as its first argument.

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I'm going to pass in two more arguments x and y.

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Now, in our constructor,

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I'm going to say self.x equals x,

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and self.y equals y.

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Now, if I delete these lines and try to run my code as this.

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Then I'm going to get a run-time error,

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saying that my constructor method takes

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exactly three arguments but only one was given on line nine.

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What that's saying is that,

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so it takes three arguments but self was already provided when we called our constructor.

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We need to pass in values for x and y as soon as we create instances of point.

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So, here I'm going to pass in values five and 10 for this point,

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and one and two for point two.

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Now what happens here is that for point one,

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I'm passing five in for x and 10 in for y.

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For point two, I'm passing one in for x and two in for y.

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Rather than setting the instance variables later on,

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then what we're doing is we're setting the instance variables in this constructor.

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So, when we say self.x equals x for point one,

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that's setting point one.x to be five and point one.y to be 10.

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When we do this for point two then we're setting point two.x to be point two.y to be two.

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So, now if I call get x on point one,

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so print point one.get x.

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Then I should get five.

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If I print out point two.get x,

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then I should get one.

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That's all for now until next time.