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>> And before we get started actually, I'd like to mention that there's

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just, you know, FYI, there's different kinds

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of verbs because what I'm looking for

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is really action verbs. So verb, verbs that clearly express an action that

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can tell me that, you know, what, for example, an item could do, 'kay?

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>> Okay?

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>> Not the verbs that represent, for example, relationships, 'kay?

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>> Okay.

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>> So, and the, there, and the ones

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that I've identified und, underlined here actually, I,

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I underlined complete sentences so that you kind of we can look at the verbs in

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in context. And the first one is this

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sentence that says that the library may need

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to know or to calculate the items a

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patron has checked out, when they are due, and

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any outstanding overdue fines. So I, I will

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imagine that this is representing a situation in

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which you bring up a patron's record and

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you start looking up this information. Is that [CROSSTALK]

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>> The, the patron often wants to know what they have currently checked out.

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>> Oh,

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alright.

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>> Or when are their due or how much they're owed or.

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>> Oh, in fact, and then now that you mentioned it,

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I think you sent me. One of the scenarios you sent

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me had to do with that, right, with the patron coming

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in and asking for this information. So yeah, and it makes

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a lot of sense. So what I'm going to do, I'm going to

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model this by adding this three operations to the patron method.

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The first one, I'm going to call, itemsCheckedOut and, basically, it's an

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operation, but you don't need to, you know, understand the implementation

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details, but when you call this operation, it will

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give you back exactly this information, so the items

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that are checked out by that patron. The second

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one, I'm going to call it whenDue. That will tell you

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basically when a, when an item is due. And

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the third one is going to be called the outstandingOverdueFines and,

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you know, as the name says, it's going to tell

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you what are the outstanding overdue fines for that patron.

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>> Okay.

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>> And as you might notice I mean,

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I, I'm going to separate the, the, the attributes

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from the operations by having a separate kind

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of subrectangle so, in this way, it's clear

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what is attribute and what is, what is

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an attribute and what's an, what's an operation.

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>> Gotcha.

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>> And let me see then. Okay, for the

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second one you can see that that patron can check

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out books and audio visual materials. So I guess,

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similarly you, you build kind of the record for a patron.

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The patron will give you an item and you will record

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the fact that the patron is kind of checking it out.

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>> Right. And is that operation related to this,

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the checked out attribute that we did a minute ago?

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>> It is actually because what will happen then again, you know, if we jump

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ahead a little bit would be that every time you invoke this operation. So I'm

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going to represent this as a checkOut operation

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for the patron. Every time you invoke this,

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you will also have to say something about the item and so we will also

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flip kind of that that, that build information in the, in the, in the item.

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>> Okay.

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>> Mm, 'kay? And, and finally, here, I can see that

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a patron can request a book or an audio video item Is

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not currently in. So I guess this is referring to items that

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are already checked out but for which there is interest. Is that?

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>> Right. So, particularly, the popular items the patrons want to get on

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the list so that they get notified when it comes back in and.

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>> Oh.

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>> And check it out.

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>> I see. I see. Okay. Then I'm going to do

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the same thing here. I'm, I'm going to add this method,

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which I'm going to call request and I'm going to put it

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here in the list of the methods in the list.

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>> Okay.

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>> Of operations for the, for the patron, okay?