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I don't know if you have noticed it, but recently we have been working more on improving the code base

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rather than improving the output of the program.

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So specifically, we used functions.

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We integrated functions in our code, even though the code was also working without functions.

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The program was working because it's relatively a small program.

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But if the program gets bigger, then you really have to use functions to be able to keep your code

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organized.

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So whenever you want to create a process, just put it in a function.

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And in this video, we will go and work even further improving our codes.

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So let's you remember the example of the barista and the coffee.

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So let's talk about that again.

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So I have a question for you.

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When you ordered the coffee to the barista, where does the barista make the coffee?

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Does he or she make the coffee in your table?

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In the table you're sitting?

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Or does the barista have a separate space where they prepare the coffee?

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And the answer is, of course, they have a separate.

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Place for that.

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Otherwise things would get messy.

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And that's what we want to do here in our court as well.

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We want to separate the processes in a separate file.

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So currently we are in Maine.

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That pie, which is this file in here.

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What I'll do now is I will right click over the project directory, which is the same directory where

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main that p y is located.

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So I will right click here and create a new python file.

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You can name this file, anything you want.

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I would like to name it just.

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Functions on my charm.

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I don't have to supply the dot pie extension because Pie chan will add it by default.

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So that is a function that p y file and I'll just go to my main dot pie file and just cut these two

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functions.

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And pays them in functions that p one.

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And I would like to open this file to the right side so you can see both files so main that P were here

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functions that P in here.

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I'll close all these.

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No, I get all these red underlined.

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Elements such as the function call here.

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So it says are resolved to reference get to dos because this script now doesn't know anymore.

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What get to do is same for right to dos.

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So they are defined somewhere else and not in this script.

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We can fix that by.

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Saying from.

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Functions.

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Import.

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Get to dos.

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Comma.

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Write to dos.

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And now the red lines are gone.

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So if I run the script, it will behave exactly the same as it did before.

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Just show that to dos.

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And here they are.

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So why did I place the functions in another file?

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Well, this is just a common practice.

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It's a good practice to do because you want to organize the code when it gets bigger.

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So it's better to have logical parts of the code in separate files so that the code doesn't get extremely

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long.

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So in this case, it's it's logical to put functions so procedures and processes in one file and that

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simply import them in here.

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That is the syntax to import.

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Elements from another file to another file.

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Now, this will work.

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This syntax will work only when main that P and functions that P are in the same directory because they

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are in the same directory.

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This file.

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Everybody knows where to find this functions.

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So that is the name I gave to my dad's P file.

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So that has to reflect that file.

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And of course, these also have to reflect the names of the functions in here.

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So those from an import are keywords which are part of this syntax.

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Now, this is not the only way to import.

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Functions.

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Another way is to just say, Well, let me comment this.

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So another way.

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Is to say import functions.

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And then you see that these are again in underlines.

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Because these names, again, are not defined in the script.

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They are not mentioned anywhere.

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When we had that line, which is now commented out, so it's not recognised by Python, when we had

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that line that meant that these were available, they became available in the script.

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But now we have to follow a different approach.

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If you do here import functions than here, you want to say functions don't get to dos.

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And I guess now this also becomes a bit familiar, this syntax.

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It becomes familiar to you.

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So that's like the same syntax that you use.

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To call methods, for example, user action that strip where user action is a string and strip is the

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method which removes the spaces from this string.

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The difference here is that this is a string and this is a module.

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So it is it is this script.

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But when you import the scripts here, then you call it a module.

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That's the terminology.

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So.

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In other words, when we are in this mean that P word scripts and we import that other scripts, we

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refer to that as the module.

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Same thing like in the coffee example.

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Where the clients could refer to the area where the coffee is made with another name and.

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The body store itself with their colleagues, they can refer to that place using their own name.

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So here in this may not be why we are in our table and we refer to that functions as the module.

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Where something happens and this group is not interested about what happens there.

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The script is only interested about getting the outputs of that.

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Of those procedures, those functions.

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So we get the outputs from there by calling that space.

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So we can get now functions.

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We can call functions from that space there.

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So similarly, we want to mention functions.

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That's right.

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To do here.

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Functions that get juice in there wherever you have this break lines.

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There and here as well.

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So now we don't have any more red lines.

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The question is which way should you use this or that?

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And that's a hard question, and it's not always easy to answer.

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It depends how many functions you have in the module here.

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So in our case, we only have two.

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But if we had more, then you'd have to write all the names of the functions there and so on, divided

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by commas.

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So if that was the case, then it would definitely be better to just import the functions module and

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then just refer to the functions of that module using functions as the first name separated by a dot.

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So that would avoid us having to import all the functions one by one.

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We could forget one of them, or it could become a long list here.

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So that's why we have this other simpler way to import a module and then refer to them as here.

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So if you have very few functions like we have here, you could use that.

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But this is also fine to use.

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And this can also make the codes more readable because by just looking at this parts here, you'll know

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that get to dos comes from the functions module, so that gives you some extra information.

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Whereas if you had only that without the.

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Comments.

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So you'd have something like that.

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In that case, it's not easy to tell if get to dos was defined in the script or in another script.

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Of course, you can look at the script and see if get to do is there, but it's easy to just tell.

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Immediately if this is from the script or from another script.

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So that's why I would suggest to use this syntax.

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Lastly, it could happen that you may have more and more files, and in that case you may want to create

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a directory.

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Let's call this modules.

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So this directory, which is in the same directory with main PI.

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Now if I drag functions that's pi and drop it in modules, Python will ask me if I want to refactor.

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So I refactor here in that case.

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Pie chart change this from input functions to from modules input functions.

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So this is the new syntax now.

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And so as you see modules reflects the name of the directory here and functions reflects the name of

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the module.

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So if you ever have directories where you place files, then you want to follow these syntax points

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to the directory name and then to the module.

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In our case, this is not necessary, so I'll drag this back to the main directory and this will you

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be used as just functions?

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So that's about creating modules and importing them.

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So this is both a script, as I mentioned.

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From.

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It's own perspective versus a script from the perspective of the other file where this is important,

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this function is a module.

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So I hope that makes sense.

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We will run a few experiments in the next video to understand some things better.

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So I'll see you there.