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When looping in Python one of the most common tools is this range function that we get out of the box

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with Python and you see here that range well is a Range object a special type of object in Python that

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returns an object that produces a sequence of integers from start to stop let's explore that are a little

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bit more if I print here a range and I say range one hundred and I click Run I get range of zero to

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one hundred.

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So it looks like a tulpa but it's not.

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It's a Range object and it's a special type of object and a range you can give it like this which gives

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you a default of zero to whatever you give it which is 100.

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Or you can just simply Type 0 one.

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And if I click Run it's the same thing but where range becomes really useful and you'll see this in

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99 percent of cases in Python is in for loops you see besides topples and lists and sets and dictionaries

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and strings.

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You can iterate over a range.

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So for example if I do for i in range and there's a say item or in our case letters to number in range

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and in here I do print no if I run this you'll see that I'll get numbers 1 to 100.

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And why is this useful.

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Well using a range I was able to loop a hundred times as you can see all the way till 99 because our

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count starts at 0 and we're able to loop as many times as I want so I can tell the loop maybe we want

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to loop a certain number of times maybe you won't want to loop 10 times where I can tell the loop how

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many times to run it's extremely useful maybe here we're performing some action where it says I don't

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know email the email list so we want to send 10 emails to an email less for example.

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Well again I can just click Run and I sent that email while a bunch of times 10 times.

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Another neat trick is that while you might not even need no great we're not really using it in our code

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and often while you'll find in python programs is If a programmer doesn't need this variable you just

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do an underscore and this is just a variable.

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I mean you could use it like this and you'll still get these numbers but it just indicates to other

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people that hey I don't really care what this variable is.

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I'm just trying to use range so that we can loop over things.

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Let's say 10 times now range also comes with a third parameter.

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And what that is is they step over.

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So if I do too.

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And by the way.

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Default is one here.

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If I do two it jumps from zero to 10 by two which is very very handy.

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So what is the range.

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Well range creates a special kind of object that we can iterate over OK.

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What if I do minus.

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Right here.

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What if I do minus one.

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Well if I run this Hmm that's not going to work because well let me show you why.

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If I change this to zero and 10 and I do minus one

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it's going to go in the opposite direction but if I did just ten and zero that's not going to work.

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If we want to do something in reverse we just have to make sure that we add that minus one or if we

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want to step back twice.

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Then we click Run.

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So you have a lot of options to play with the range.

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You can do ascending descending one final thing.

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Another place that you might see ranges.

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And like I said most of the time they're in for loops but he can also do something interesting like

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let's say a range of 10 and then if we wrap this in a list remember a list function allows us to convert

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something to a list.

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If I run this does you see that let's simplify this so that this range is going to just be too if I

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click Run you see that I loop two times and in here I'm going to print first of all I'm going to create

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a range and it a rebel object that has 10 items and then I'm going to convert that into a list so you

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can see here zero to nine into a list.

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So this is a quick way to create a list that ball has integers a neat trick that you'll definitely use

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along your program or journey I'll see in the next one.

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But by.