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In order to finalize our understanding of functions we have to talk about scope.

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Another one of our key terms what is scope let's have a look

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scope is something present in a lot of programming languages and scope simply means what variables do

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I have access to.

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So what do I mean by that well we've seen this before right where I do print and then let's say Nate

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if I click Run I'll get an error a name error name name is not defined because well it doesn't exist

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right.

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And up to this point we haven't really discussed this but this is because of scope what variables do

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I have access to the Python interpreter says hey what do I have access to.

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And when we use something that it doesn't understand or doesn't have access to it's going to throw a

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name there or a variable is not defined our and scope in Python has what we call functional scope or

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function scope.

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What does that mean.

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Well up until now when we create a variable like total equals to a hundred.

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This is part of what we call global scope.

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That means anybody on this file has access to this total variable.

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I can use this inside of a conditional block I can use it inside of a function.

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It has global scope but when I say Python has function scope what I mean is that when we create a function

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and let's say we create total as some or let's say some func and we create total inside of the function.

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If I print Total here and I click Run I get the same thing name.

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Total is not defined.

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This is because of Python's function scope.

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Anytime we create a variable if it's not inside of a function then it is part of the global scope.

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We have access to it.

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But you see over here we get that red underline undefined name total.

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If let's say for example I had a condition if true then X equals to 10.

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If I do this and I say X and I click Run I have 10 because well although I have indentation the only

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time I create a new scope you can think of this as a new universe that we spot.

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Well we can only do that when we define a function like this.

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So think of scope as a new world that we create in our case when we create a function we create a new

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world that anything that's indented inside of the function is its own world that we don't really have

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access to.

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We can only use total if we indent print and it's part of this world.

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That's what scope is.

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Who has access to who.

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So let's take a break here and I want to play a little game in the next video where we try and figure

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out who has access to who.

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I'll see that one by.