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Instructor: Welcome back.

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I kept mentioning this key term, iterable,

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but what does it really mean?

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Iterable, you're gonna hear that over

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and over in Python programming

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and other programming languages as well.

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And as we discussed a little bit in the previous video,

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iterable simply means it is an object

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or a collection that can be iterated over.

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So again, an iterable can be a list,

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can be a dictionary,

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can be a tuple, can be a set.

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It's a collection of items.

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We also saw that a string could be iterable.

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Now these things are iterable.

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Why?

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Because they can be iterated.

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That is iterated means that we can go one

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by one to check

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each item in the collection.

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And you're gonna hear this

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over and over when talking to Python programmers.

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So you wanna make sure that you have that vocabulary.

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You're iterating over something,

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you're looping over something.

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So iterable is the noun

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and iterated or iterate

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is the action

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of iterating over an iterable.

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I know, it's a little confusing.

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Now, many objects in Python, like I said, are iterable,

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but there's a few special ones that we haven't covered yet,

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specifically, dictionary.

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We saw how lists, tuple, sets, and strings can be iterated.

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But what about an object?

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Let's say we have an object here,

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and this object will be users

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and users or user

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will have a name of Golem,

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will have age of 5,006,

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Golem's, pretty old.

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And then we'll say, can swim Golem,

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let's say, cannot swim, false.

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What if we use this object right here

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for item in user and we print

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right here, the item.

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What do you think will happen?

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Let's run this.

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Well, I get an error because I forgot a semicolon here.

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And we don't want Eagles, we want semicolon.

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And then obviously, this needs to be a string as well.

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Now if I click run here, look at that.

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I get name, age, and can swim.

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So I've printed the keys of the dictionary.

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Now this dictionary, we have the keys.

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That's great.

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But, hmm, what if I wanted actually the values?

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Is there a way to do this?

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Well, dictionaries have three methods that are really,

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really useful when we wanna loop over

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their keys and values.

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The first one is items.

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And with items, when I do this and I click run,

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you'll see that I get the key value pair

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in a tuple.

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And this is a very common pattern that you'll see a lot.

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Another one that we have is values.

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And guess what that does?

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That gives us the values

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of the dictionary.

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And we saw that user just leaving it blank gives us

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the keys, but we have a method that is more descriptive

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and allows us to show exactly what we wanna do,

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which is keys.

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And if we run this, you'll see

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that I'm able to iterate over the keys.

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And these three methods are very common

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and you're gonna use them a lot in your programming career.

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So make sure you take note of them.

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Items, values, and keys.

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It allows us to iterate over dictionaries.

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But another interesting thing that you can do

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and another common pattern when iterating

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over dictionaries is what if you wanna print for example,

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separately the item's name and Golem.

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So right now, we're returning a tuple

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and we saw that we can do tuple unpacking, right?

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I can say,

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key value equals item

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and then just print key value.

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If I run this, you see that I'm able

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to print these,

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but there's actually a shorthand way

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of being able to do this.

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In here in the for loop, I can say key value

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and just completely avoid this entire line.

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And if I run this,

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there you go.

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It still works.

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And this again is a very common pattern

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where if you're collecting the items of a dictionary,

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you can separate them into key and value,

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or you might even see shorthand KMV.

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Again, these can be any variables that you want.

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You can name them whatever helps your code

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be more readable.

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By the way, just for fun, let's say,

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in the last line here, I wanna iterate over the number 50.

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What do you think will happen then if I click run?

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Sorry, name error, name key.

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Oh, I get an error here

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because I haven't changed these, so let's change these back.

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That's not the error I was expecting.

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The error I was expecting was this,

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TypeError: "int" object

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is not iterable.

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Now, this error should make sense now

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because I've said it over and over.

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Why is it not iterable?

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Well, because it's not an object that can be iterated over.

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It's not a collection of items

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because we learned that in Python,

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these are iterable.

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I'll see you in the next video.

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Bye-bye.