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In this video, we will write a script which redeems all the files inside the files directory.

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Specifically, we will adds a prefix to all these files.

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So by the end of this video, these files will have been renamed to something like New Dash A, B,

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C, C, New Dash D, F, the taxi, etc..

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If you follow the previous video and you should have done that, then you know that we will be using

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path lib, specifically the path class of path lib.

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So how do you go about implementing this?

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How do you rename all these files?

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Well, whenever you have to manipulate files or directories, change them, rename them, copy them,

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delete them first.

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You want to determine where these files are in Walt's folder.

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What is the root directory?

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So in our case, what is the root directory?

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Well, our files are inside these files directory.

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Therefore, the root directory, which is a variable that I creates, is path.

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So I'm creating a path object instance with files as a string.

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So with that, now I have the files directory as a path object and I can go further and create.

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A lease or file paths using routes, they're dot, it's dear methods with parentheses.

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And just to demonstrate you what we have this far.

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I'm going to convert this file paths generator into a list because you know that from the previous video

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that these methods outputs a generator, so least file paths.

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And let's see what we have.

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Yeah.

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So we have this list of all the files that we want to rename.

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Right.

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Three files so I can go ahead and delete that print function.

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And then guess, what should we do now?

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Well, you guessed it, it's a full move, so full path in file paths.

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So we will go through each of these three five paths.

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The first one, the second one and so on.

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And what do we want to do in each iteration?

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So our goal again is to rename each of these files.

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Therefore, I think we should first think of a new name.

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So to construct is trying to represent the name as a string of can we construct a path that points to

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that's new file name.

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So that's new file, actually.

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So I file, for example, this file, it's a file on disk and in Python, this file is represented through

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a path file path, and this path object is represented through a string.

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So there's a chain of objects, right?

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So the new file name is going to be new dash plus path dot.

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STEM plus path, dot suffix, let's print file name, new file link to just see what we have.

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Run and this is what I intended to have as the new file names, but of course, don't expect these to

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be changed by now because we didn't manipulate any paths, right?

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We're simply iterating here, constructing a string of than we need to do something with that string.

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So let's delete print the way this works.

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I think it's clear.

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So we have a strong new path.

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The stamp gives you only the file name without the extension.

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So ABC.

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So we have new Dash ABC that takes you.

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This gives you the extension of the file name for each file.

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Right.

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So we said now we need a path or five path, whatever you like to call it.

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So I tend to name.

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The valuables that points to path objects using paths at the end, some paths here or path here, and

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you see here this is a string, so I named it differently.

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So a new file path, we said it's a path object.

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Right?

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And the argument is the string, so path classes get string as arguments.

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Right.

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In this case, it's new.

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File name a, but we need to add something else here, so it's not exactly new file name.

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This will cause us some problems and I want to show you this problem now.

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So that's you learn a very important points related to manipulating files and folders.

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Because see what happens now if I try to rename.

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The path, so path is this one in here, which means it is the current path of the loop.

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So one of those here and if I rename that path by giving it the new path as argument, so rename it

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the methods of a path object.

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And it gets another path object as outputs.

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If I run this group now, you're going to see some maybe strange outputs, but it has an explanation.

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So what happens is that the files are not inside's files anymore.

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You see, files is empty.

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If I collapse the folder, these files now are outside the files path.

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They are in the main or EPFL directory, not inside files.

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So what happens is that this new file path, what it is, is this a printed for you?

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Print new file path run.

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No outputs, because now files is empty.

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But let me drag them inside files again as they were before and run the script without renaming.

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So Ron, this is the output we get from printing out the file path.

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But because the current working directory is set to the rebel directory.

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And not to the files directory.

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These files are read something that's readable directory.

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So the current working directory, you see, that's if I print out print path, that's c w d and call

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that method and run.

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This is a current working directory where Python is working on of the moment in this script.

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And that means.

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This new path will be appended to that working directory.

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So the complete path of this new file path will be something like home run.

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Rename all files to slash new new ABC books.

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That's why we see those files written in the main directory, which is rename all files to.

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To change that, you need to follow a different approach.

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So instead of doing this here, we point to the existing path dot with name and the name is new file

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name.

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If I run this script now without executing rename just yet, if I run this, this time we'll see files

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is appended before these.

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Therefore, this file named this file path will be appended to this and therefore we're going to see

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the correct outputs.

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So a new text is added to the existing was right.

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Just to be clear, rename this to the original was.

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Like that's and uncomment very name.

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Methods so new file name your new file path in here.

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New file path in rename and run.

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And these are the three renamed files.

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And this is the correct altitude.

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So that's was about this video there are a few key points to take from this video.

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So the first one was that you want to work with path objects.

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So if you have a string that represents a file path in disc, then you need to create a path object

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type using that string and then be careful with current working directory of the current working directory

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is always where your main supply file is located and Main does profile is located in this directory.

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Therefore, if you want to write in, your files are already name files.

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You want to make sure that the new file path that you're already naming.

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Has the correct path.

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And in our case, the correct path was files slash new Dash, A, B, C, D, S T and so on for the

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other files.

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And we did the trick with this part here.

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So path with name, that means that we created a new path here from the existing path, but with a new

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name.

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So basically, this says give me a better path with a new name for the file port, and we set a new

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name in here and then we renamed the existing path.

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Giving vets new name, I hope that it's clear, and I'll talk to you later.

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Thank you.