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Welcome back.

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Let's try it.

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A simple exercise.

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I want you to build a simple counter and this counter is going to count the items in our list.

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What does that mean.

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Well let's say I have a list and this is a reserved word.

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Remember it's an actual word in Python so let's name it my list as a variable.

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And this list has 1 2 3 4 5 6 7 8 9 what I want you to do is using looping to loop over this editable

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list and sum up the total of the list pauses the video if you need to.

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Otherwise let's see how we can do that what I'll do is create a counter variable that will equal to

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zero to start off with and then I'll say for item in my list I'm going to counter equals counter plus

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item and then at the end I'm going to print counter.

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Let's see if this works I'm going to hit run and I get fifty five which if my quick math is right should

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be should be correct.

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Now when doing this exercise you may have gotten tripped up a bit.

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So let's think about this.

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Some of you may have made an error where you did the print here but if you did the print here you remember

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that it's going to get looped over it's part of this code block because of the indentation and it's

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going to print as many times as there are items so you have to make sure that the indentation is like

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this so that you get the total.

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The other thing that you noticed is that in order for you to keep a counter or a total of all these

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items you had to make sure that you had a variable outside of the loop because the loop runs the code

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over and over and you needed something on the outside.

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That doesn't change because if you moved the counter to zero here well every time the counter would

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be reset to zero.

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So that by the time we get to 10 counter would be zero.

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So you get zero plus 10 which equals 10.

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And then you'd get well 10 so you have to be careful here that the indentation is an indication of us

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looping and when you loop something and you want to keep a tally or total of something that you have

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these issues of making sure that what you want to loop over is inside of this code block but why you

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don't want to if you want to have some sort of information that's outside of this loop that you keep

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it like this if you weren't tricked by this question.

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Good job if you were.

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Don't worry it's all part of learning.

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I'll see in the next one.

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Bob.