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Hey, welcome back.

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In this video, we will make our program a bit more user friendly because currently we get these break

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lines here, which it's not so good to have from the user perspective.

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So let's remove these break lines.

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But how do we go about this?

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Again, introduce the text.

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We don't have these break lines.

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Actually, we have break lines, but only one break line.

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So there is a backslash n after prepare and then there is another backslash n after shower and so on.

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So the extra break line is being produced by the print function here.

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So we end up with two sets of break lines for each line.

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So how do we go about this?

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Do we remove the brick lines from the text file or we do something in here?

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Well.

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Of course, we shouldn't edit the text file.

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We should edit the representation of the data that is in the text file.

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So the representation is the list.

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Therefore we should add it to the list.

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So that's the case.

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BLOCK And here we get.

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The to do list from the text file and then we iterate over that to do list.

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But now a solution we could think about is to remove.

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The backslash and characters from the list.

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Because currently, if we print out the list here, we execute the program again, we press show, and

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this time you're going to see that that's the print function that I've just added.

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So that print function produces that list.

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So the list has these backslash characters.

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And then the loop add some more.

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So let's remove this back slashes and then we fix the problem.

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So we remove the backslash from each item.

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Therefore, the loop will only produce one backslash.

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The backslash that it produces by default and it will not have any other backlashes.

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Therefore, how do we add it?

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Each of these items.

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So how do we perform batch operations?

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You learned four loops earlier in the course, so that is something you can use.

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There are two solutions for this actually.

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One is for loops and one is list compressions.

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And we're going to go through both.

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So let's first start with for loops.

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That's the existing list.

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But what I'll do is I'll create a new list here.

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So in the same indentation level, let's say new to dos variable is equal to an empty list.

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And then what we do is.

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We iterates over four item in to dos.

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We iterate over to dos so our item will be each item of the to do list, including the backslash n.

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And then.

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We say new.

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It will be equal to item that strip.

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Backslash.

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And so that's command.

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What it does is, is this.

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So let's say item will be equal to.

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Prepare.

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Backslash n.

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Therefore new item is equal to item strip.

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Backslash.

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NW So a new item now is going to be equal to just prepare without the backslash N while item is that

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one so new item will be without the backslash.

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And then what we do is we access new to DOS that append and we add new item there.

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So we're going to end up with a new list which is going to contain the items without the backslash and

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characters.

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Then what we could do is in here we iterate over new to dos instead of.

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To reduce.

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And that's with solve the issue.

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So now let me rerun the script.

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And type show.

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And these are the two do's.

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We also get the lists here from that print so we can remove that print function.

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We don't need it anymore.

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So that is one way to do it.

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Another way to clean up the list is to use a list comprehension.

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A list comprehension is the equivalent of a full loop.

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So it's just another way.

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To modify the items of the list, but it's a shorter way.

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You'll see why and list comprehension.

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All it takes is one single line, and it starts always with square brackets.

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So inside here you write an inline four loop, so a four loop in one line you would say item that strip.

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Backslash n.

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So that is one expression.

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And you say for item in.

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To dos.

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And this is going to be new to dos.

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So this is basically a list.

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I am going to remove these.

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We don't need them anymore.

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But before I remove them, just try to compare the full loop with this.

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So basically what we're saying is that you can start reading this from here to understand it.

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So for Autumn, introduce.

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You iterates over the to do list store item that strip backslash and in this list.

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So this will return an item without the backslash and so this item will be part of the list and this

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is repeated over the other items.

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So we end up with three items.

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As part of this list.

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So this will be just a list.

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So let me delete that now.

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And the declaration of the new to do list.

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So with the list comprehension, you don't even have to declare an empty list.

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You create the list on the fly using the list comprehension.

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So run.

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Show.

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And we get the same exact output using a list comprehension.

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However, perhaps we didn't even need to use a list comprehension here.

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We could apply a more direct method to remove the backslash and characters from.

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These to do items.

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So that way would be to delete this.

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The way is to iterate over to DOS as it was.

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So this was the code in the beginning of the video which produces again.

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These items with extra brake lines.

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And then what you could do is.

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You want to override the item variable?

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You could do something like item is equal to item strip.

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And then here you place backslash n.

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And then this item here will be the new string without the backslash n character.

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So let me try this solution as well.

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And here we go.

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So I suppose this was a simple solution, but.

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This was a good opportunity for you to understand.

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List comprehension.

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So whenever you want to modify.

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The items of the list.

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You want to use a list comprehension.

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And of course, luckily or unluckily, sometimes there are more than one solution to do something.

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Which one is the best?

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Well, it depends.

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You should think about readability, but also.

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Efficiency.

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So how code, how fast your code runs.

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And there are ways to measure the speed of your code.

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And we'll cover that later.

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For now, it is important to learn all the core elements of the language.

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So thank you for following this.

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I'll talk to you in the next videos.