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In previous lectures, you learned how to create and use sequencers and dictionaries.

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These are collections of multiple items and this is actually showing you how you can look through those

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collections so that you can process each of them containing items individually.

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So in the Python three documentation, there is Section five point six that talks about looping techniques

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in some of those who going to show you in this lecture.

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But you can go here for more if you're curious.

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All right.

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Let's go into our examples.

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Let's start with Rangers'.

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A couple of years ago, you learned that in order to create a range, you can use the range function.

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In this case, I'm using it with three parameters.

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So I'm going to create a range of numbers from zero to 50 50 non-inclusive step five account.

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So now to print out the individual items in this range, I can just print out the range itself.

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Show what happens if I do that.

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So if I just say print range of zero to 50, that's the name of the variable that I'm using here.

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What I'm going to get back is just the object.

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In order to print out the individual items in the range, you need to use a loop and to do that, going

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to create a loop using the full keyword, I'm going to give it a variable so that each time we go through

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the loop, the current item out of the loop will be stored in this arbitrary variable.

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So this name here is a variable.

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I choose to hold that current item that we are browsing through the range in this case.

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So this is going to be in this range zero to 50 step files.

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And this is going to be a block that I'm creating here.

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And that's why I need to finish with the column that dots Sony realizes that I'm creating a block because

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I've just finished with the column.

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So here I just want to print out what's inside.

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So the value stored in a number variable, enter and then enter again to get out of this block and the

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interpreter will just immediately execute my folder and print out the individual.

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Items out of this sequence.

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That's how you can create a loop from a range.

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Let's do something similar now, but this time for a list.

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So I've got a list of letters, which is this one here.

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We saw this for the first time a couple of years ago.

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So we got a list of letters to iterate through it in a loop.

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Use the exact same methodology.

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The only difference is that instead of a list created by the range function, we've got a list that

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we have explicitly created that contains letters, so say for later in the list of letters.

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Print out.

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Enter and enter again, and there are my three letters to exactly the same methodology for both range

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and lists.

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What about tuples by name?

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You can probably guess that when we are looping through a tuple, the method we follow is exactly the

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same as if we are looping through a list.

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So we're going to use it for keyword.

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We're going to go for just the generic word item since this list contains both numbers and letters.

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I'm just going to go for item and then the name of the tuple in this case.

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The.

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Interesting, so.

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I made a mistake here, did not include in and I just show you what happened could completely normally

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works unless there is a problem with the syntax that you're using.

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So I will go to you in here.

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And I went to use Teppo and then the code completion.

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But there's and nothing is happening.

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That's because the syntax broken.

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But if my syntax is correct, then code completion will work correctly as well.

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So is that a gotcha?

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All right.

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So then you can just print the item.

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And we have to loop goes through each item of the tuple and print it out.

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Now, the last thing that I want to show you, of course, is a dictionary.

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We can use dictionary in a slightly modified way because remember, the dictionary contains keys and

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values.

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So we can't just use a single variable, temporary variable here because we've got two things that we

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want to capture.

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We've got both the key and each value.

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So to make this work.

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Again, we start with the four key word, but then we say key value.

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And of course, these are arbitrary names.

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You can go for whichever name you want for the key and the value and the rest is the same.

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So we go for E.S.P three to six dictionary.

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And then for the print, we've got two things to print out now, shall we say, key comma value, and

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that's a mistake.

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What happened?

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Yes, it did make a mistake.

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So there's one more thing that I need to do and take a step back.

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So if I tried to print out a speech, 30 to spec dictionary, what you'll get back is a dictionary like

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this.

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But what we want to do instead is to get the items out of this dictionary like this.

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So now we have a dictionary items object, which looks like this.

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And therefore, in my loop, I want to use the items version of the dictionary.

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So let's try this again.

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I'm going to copy you save a bit of time and get the items for my loop and then print those items out

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sophisticated and then devalue it since and now we've got to manufacture a key and it's value, that

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type key and each value and so on.

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And that's how you can loop through sequences and dictionaries and put in.