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By the way there is actually one more way that we've actually seen in list how to look for an item in

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a dictionary remember how in lists we use the keyword in we said something along the lines of Hey is

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I in a list that contains I or we even used a string like Hi.

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Well you can do the same with dictionaries.

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I can say does basket exist in user and let's print this out.

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And run and it's going to say yep basket does exists in user.

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What about what about the size.

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Does that exist.

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No that's false.

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That does not exist in user.

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But here is where it gets really interesting.

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And this again is a nother dictionary method that we can use.

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And by the way you can see that there's not that many dictionary methods that well dictionaries have.

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Luckily we're gonna go over the main ones here though one is called Quis and keys simply checks the

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keys.

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What are the keys of user.

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So if I go Hello here and I click Run well no keys ha sorry on this side not this.

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So this is a value.

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So if I want to check keys I'd say H which is true but if I want to check a values well in that case

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if I do.

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Hello I get true it's going to go over or what we call iterate over the values another one that's really

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useful is the items and items is special because we've seen keys and values but items actually grabs

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the entire item.

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So the way we can actually see this is let's just remove and click Run All right.

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This is interesting.

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I have dict items here and I grab looks like a list and in here we have a bracket basket.

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One two three greet hello and H20 but there's some weird syntax here that we haven't seen before and

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this is actually a topple.

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So we're going to hold off on this and talk about this a little bit more when we talk about our next

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data structure but keys values and items is an easy way for us to grab these things for us from our

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dictionary let's continue on with other dictionary methods that we might use.

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One is a very nice one.

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It's called Clear.

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And if I run this you'll see that I get an empty dictionary.

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What if I just run users dot clear here and run.

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User Well it's still an empty object or an empty dictionary so you can see here that clear doesn't actually

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return anything.

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It doesn't.

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Well it is just in place removes whatever the dictionary has.

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So it just creates an empty dictionary.

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What about copy while a copy allows us to copy a user so that if I print user and user 2 and I click

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Run I get two users each.

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Keys and values copy.

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But if I now let's say clear the first user and I click Run the first user is empty but because I've

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copied the second user the second user has the old information and this is a concept that we've talked

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about before.

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Another useful command and let's just go back to having user is user dot pop which removes a key and

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a value from the dictionary.

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So in our case let's just say we want to remove the key that is age so I'm going to say h and if I run

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this I get 20 because pop returns the value of whatever got removed.

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But if I do print user now you'll see that age does not exist anymore because we've popped it off but

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pop as you can see removes the actual value or returns the actual value 20.

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Here's another really fun one pop item.

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And honestly this I having used much but I just think it's a fun one pop item.

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If you guessed Well you're not gonna guess oh and that's because I have to make sure I write it properly

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with lowercase if I run this would just happened it randomly pops off something one of the keys and

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the values in this case age 20 is removed.

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So the last item on the dictionary gets removed by remember a dictionary is unordered.

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So if this was a massive massive dictionary that well doesn't have any order to it sometimes it removes

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some pear as you can see not the last one but some pair of key value so you have to be careful with

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this one.

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It doesn't necessarily just remove the last thing that you entered but it might be useful on some occasions.

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Finally we have something called update an update simply updates as the name suggests a key value so

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let's have a look here.

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All we have to do is give it a new dictionary so curly brackets and just simply say hey I want to update

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age to fifty five fight click Run Oh and I forgot a bracket here.

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Let's try that again.

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If I click Run.

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There you go.

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Age got updated but if this was a key that doesn't exist like ages and I click run it will still update

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with a new key item.

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So this is another really useful method.

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All right that's it for dictionaries.

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I'll see you in the next video.