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Now, unlike some other programming languages,

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if you've come from say C++ or Java,

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there is no such thing as block scope in Python.

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What this means is that if you were to create an if statement,

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say if 3 > 2,

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and if you were to create a new variable inside an if block or a while loop or a

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for loop, basically any sort of block of code that's indented,

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this does not count as offence.

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It still has the same scope as its enclosing function,

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or if there is no enclosing function then it has global scope.

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So let me show you a full example. Let's say we had a list of enemies,

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so the enemies could be skeletons, zombies, or aliens. So now,

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if I was to define a game level, right?

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Like the level that the user is currently playing at,

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let's say they're on level 3.

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And I create an if statement and I check if the game_level is less than level

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5, well, in that case, I want to create a new enemy,

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but I don't want the enemy to be too difficult to beat.

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So I'm going to pick from the list of enemies and I'm going to pick the first

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one. Notice how,

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even though this new enemy is a variable that's created within this

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if block, if I go outside the if block

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so I'm not indented at all anymore, and I try to print this new enemy,

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this is perfectly valid code. And if I run the code,

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you'll see skeleton being printed.

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But notice how as soon as I embed this within a function,

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so let's define a new function.

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And now this line error is out because within the function there is local scope.

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So now this new enemy is available anywhere within this function,

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because blocks like if, while, for, all of these blocks of code with colons and

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indentation, they don't count as creating a local scope.

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So in order to print this new enemy,

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I actually have to be within the boundary of this function,

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which means my code has to be here.

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The most important thing to remember from this is if you create a variable

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within a function, then it's only available within that function.

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But if you create a variable within an if block or a while loop or a for loop or

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anything that has the indentation and the colon,

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then that does not count as creating a separate local scope.