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In this video, we will add a complete feature to our program, complete meaning allowing the user to

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mark a to do item as complete as done.

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So then that item will be deleted from the list of to dos.

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For this, we're going to be using a case complete statement.

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So if the user enters add show edit complete in case of complete, what do we want to do here?

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So this is the logic here.

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When you want to manipulate something in this case, we want to manipulate the list.

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So if the user enters complete, we want to modify the list.

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So we want to remove one item from that list.

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That is a manipulation process.

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And when we think about manipulation, we think about methods.

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So if I was you to find out how to remove an item from a list, I would open a python console and use

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the function and enter the list there.

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That will give me a list of methods.

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So I'll take a look here.

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Perhaps I find something like remove.

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Yo, here is a remove so I might then ask help for lists.

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Remove to see how remove works.

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So this gets a value as argument and it removes the first occurrence of value.

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Value is that.

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So then I'll try this.

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Maybe my list is equal to.

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A, B, and C.

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So my lists, you know, the notation of methods that remove.

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And that the value.

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Well, this means by value they mean the item.

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So maybe be and then try my list.

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And B is gone from my list.

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So that is one way to find out what methods you need.

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Another way, of course, is to use Google.

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So if you did a search on Google, a simple search such as methods to remove items from Python lists,

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you would get some answers.

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For example, here it says Clear pop remove.

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So it seems there are other methods as well.

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So Google search.

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Some Internet research might give you more answers to your questions.

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So clear and pop.

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You can also find these in.

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Dear.

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So you see?

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Clear should be here.

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Here is clear and pop as well, so you might want to try this out.

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Help list.

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That's clear.

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Remove all items.

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So perhaps that is not what you need.

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But anyway, this is how you learn.

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So you experiment with things.

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You research.

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Try out, list that pop.

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So in case of pop, this removes and returns item at index.

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So in the case of pop, the argument is an index.

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It is not the item itself.

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So that means you could use pop as in my list that pop.

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And if you say one here, C is removed and it is also returned.

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So you see this method returned the removed item.

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And if you check my list now, it only has a.

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Now, perhaps you might be wondering what is minus one?

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Well, this is a default value of the argument.

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Meaning if you.

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Half again, my list is equal to A, B and C, and you simply say my list that Pope, without any arguments,

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that means minus one will be the default argument.

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Minus one corresponds with the last item.

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So less indexes has another system besides the default system, which means zero index for a an index

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of one for B and an index of two for C, You can also specify indexes like minus one for C, minus two

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for B, minus three for A, and so on.

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So my list, you get that?

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So we have two options to remove or pop.

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Let's see which is the one we need so complete.

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And then we say if the user enters complete, then we want to ask the user.

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Perhaps this same question here.

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So indented with tab a number is equal to and input number of the two due to edit.

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Well, let's change this to complete.

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So we prompt the user with an input function and we convert that the user inputs to an integer.

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So the user will enter one, two or three or four.

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And so we have the index of the item we want to remove to complete.

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Then what we do is we point to two dos dot pop.

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Number.

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So that's the thing we did here as well.

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We remove the item with that particular index.

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So let's see how this goes.

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Type add, show or edit.

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Let's add some items.

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Clean add.

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Through show zero four.

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Clean one four through.

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So let's place one presenter.

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And let's show now the items.

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Oh, that didn't work because I entered one when I was asked to enter, add, show, edit or exit.

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So I should enter complete here first and then one so complete.

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Then we get asked number of the two due to complete.

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Let's say one.

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No.

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And then we say show so clean is remained and through is removed.

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Now something quick we might want to improve here is to start the list from one and not zero.

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So for that, we need to go to the show case.

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So from index item in enumerate, we say that index and here we say plus one.

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So if we do that rerun, we say add.

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Fleeing at.

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Do and then show.

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Now this will start from one, two and so on.

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And then in edit, we subtract one so we compensate for.

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That's increase and we should do the same in here.

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So number minus one.

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So that should be okay now.

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So let's try again at do at, clean at.

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Paste and.

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Show.

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One, two, three.

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We want to complete item with index.

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To so show.

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Yeah.

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So clean was the item within the zoo.

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So we removed that item and now we have to do and paste only.

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Another improvement is we want to add edit complete here or exit so that it shows in here.

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Yeah, let's check that quickly.

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Yeah.

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Here we go.

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Complete this part of the query now.

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And so this completes this video.

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That was the complete feature that we added.

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Let's keep on improving the app while learning new Python core features.

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I'll talk to you in the next video.

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Thank you.