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Add Items
5:04Let's get that list populated!
All right, so what's next?
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Let's get that list created.
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I'm gonna pull over this.
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As a user,
I should be able to add an item to a list.
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Let's do it.
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So in our shopping list here I
think right out of the gate,
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we should Create a new empty
list named shopping_list.
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Let's do that.
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You know how to do that and
then after we make
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that new list,
we should make a new function.
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We should Create the function named
add_to_list that declares a parameter,
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Named item.
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And then inside the body of that just go
ahead and say Add the item to the list.
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Awesome, and then finally let's go in and
we'll call that function right about here.
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We'll go down here.
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We'll call that function, so
we'll say Call add_to_list
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with new_item as an argument.
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All right, that make sense?
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We're going to come up here, create
an empty list, we'll create a function,
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we'll add the item to the list.
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Makes sense, right?
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You got this.
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So here, get ready to pause me and
you give those a go, one at a time.
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Then I'll let you know before I start
the next one if you wanna peek after
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each step.
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But I know you can do this, ready?
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Pause me.
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So how'd you do?
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So creating an empty list looks like this.
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You say shopping_list = [].
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All right, and now for the function.
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So we are going to define a new
function named add_to_list.
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And it declares a parameter name item.
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So there we are and
there's a colon to get to the body.
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I'm gonna add the item to our list.
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So to add to the end of a list,
you append, right?
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So we're gonna say shopping_list.append
and we're gonna pass in that item.
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Awesome, and finally, let's call it.
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So we will say down here,
let's call that add_to_list.
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Basically, anything that's come through
here, and made it down this far,
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we're just gonna add it to the list.
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Sounds good, and since we are doing
of all of our checks here,
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we've got a thing set up.
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We're pretty much protected from
commands making their way through.
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As long as we are diligent
about using break and continue,
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this will only be proper items.
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It seems like it's working, but we don't
have a way of showing the list just yet.
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But let's see,
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is there something else on the board
we can tackle before we get there?
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As a user, upon adding an item to a list,
I should know the total length of my list,
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so that I don't go buy.
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Boy, I didn't edit that very good.
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I don't over buy is what
I want that to say.
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So that I don't over buy, this is
important part of the communication there.
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So that I don't overpurchase is
probably a better word than that even.
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All right, so as a user, upon adding
an item to a list, I should know the total
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length of the list so that you're
there's a 100 list things on this.
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We don't want that.
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So let's do that.
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So let's just put that in the add_to_list,
right?
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If we come in here,
right about here, right?
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Don't you think?
So we'll say Notify the user that the item
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was added, and state the number
of items in the list currently.
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We don't want them to over buy,
[LAUGH] over purchase, got it?
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All right, pause me, go for it.
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How'd you do?
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Here's how I did.
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So I said print.
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And then I said Added: List has {} items.
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Format and we are going to get the number
of items by passing it to len.
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Here we go.
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Did I close them all out?
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There we go.
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Awesome, so let's give that a run.
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We'll say python shopping_list.
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And I wanna pick up some apples.
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1 items, a common bug.
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And we'll do bananas, and now we can
forget about it because we got 2 items,
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awesome.
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But the items are adding, so I think we've
got some tickets to complete, don't you?
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So I should be able to add items to list.
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Let's go ahead and do that.
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And as a user, upon adding an item,
we know how many are there now.
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Awesome, and
I'm gonna type DONE because I can, DONE.
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Let's knock out those last few
issues right after this quick break.
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