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Okay. When we talk about the word 'package', and what I'm saying here

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is a package,

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it's a Python package.

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And really, all a Python package is, is a collection of modules,

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just a collection of Python files.

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Really, that's all it is.

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It might have some non Python files in there, but really,

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you're just looking for the Python files.

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So usually packages are put into their own folders, and

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and they use many files that relate to each other.

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So what I'm going to do, is I'm going to open up my Desktop

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entirely, and create a new file in here.

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So I'm on my Desktop.

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I have files that we've seen before throughout the rest of this course.

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I'm going to go ahead and create a new folder in here called 'MyPackage'.

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Now, we need to tell Python that this is not just a regular

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folder, and that this is actually supposed to be a package. So,

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what we do is we create a new file in here.

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So I'm going to create a new file called '__init__.py',

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and this file is going to have absolutely nothing in it.

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This simply just tells Python,

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"Hey, you know, when you go to look into the MyPackage folder

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and there's an '__init__.py' in there, just treat it as a package, please.

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So once that's created, you don't have to do anything with it.

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Now, I'm going to create a new file in here

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called 'my_functions.py', and give it a name up here,

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'my_functions.py', and by the way, this is not necessary.

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I just like seeing that.

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It also helps viewers see which file I'm in a little easier as well.

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I know it's here and here, but sometimes that's not totally

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apparent. I'm actually one of those people that even though

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it is right there, sometimes my eyes just don't see it,

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so I like to put it there as well.

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And you never know what other text editors people are going to

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be using when they download these files, so

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anyways, that is my explanation of why I write that up

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there. And now in here, I'm going to create a new function

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completely, and I'm going to call it 'a_new_function()',

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and all this is going to do is say, 'print(

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"This is from my_functions.py")'. That's it.

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I'll make that a tad smaller, too.

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Now, beside the 'MyPackage' directory, I'm going to create

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a new file in here.

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So I'm just going to copy this over, and I'm going to call

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this 'package_program.py'.

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Delete all that. 'package_program.py'.

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And so here I've got 'package_program.py', and it's living

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beside the folder called 'MyPackage'.

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Now, what I can do, is say 'from MyPackage.my_functions',

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and you can see that VS Code is actually trying to autofill that for me,

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'import', and what am I trying to import from here?

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I can import a function called 'a_new_function'.

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Let's go ahead and import that.

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And let's simply run that as a function.

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[no audio]

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So I'm in my Desktop here, and we can see the files that I have.

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And I've got 'MyPackage',

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that's a folder; and 'package_program',

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that's the file that we're using right now. So,

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'python package_program.py', and it says, "This is from

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my_functions.py'.

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And so really, all we've done here is very similar to what

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we did with a module,

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but instead of just being in another file, we said it's also

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in another folder, and we can do this on and on and on.

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So if we wanted to, we could create a subfolder in 'MyPackage',

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create a new folder, call it 'MySubFolder'.

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[no audio]

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In here let's go ahead and create a new file, '__init__.py',

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and let's create a new one in here called, a new file called

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'subfolder_functions.py',

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and in here we can create

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[no audio]

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a variable. So let's create a variable, sort of like a constant,

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and in Python, we don't actually have constants,

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but what we do have is a naming convention.

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So instead of saying a variable name is like, 'name =',

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something, when we have a variable that we don't want to change

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we usually use uppercase, and that tells us that it's supposed to be a constant.

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So I could say 'COURSE = "Python for Everybody".

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And in here I can have a function called 'which_course_is_this',

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and due to scoping, we know we have access to this,

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so we can just simply say, 'print(

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"The course is"

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[no audio]

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COURSE)'. So let's go back here, close that file 'package_program',

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let's also do 'from MyPackage.MySubFolder.

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subfolder_functions import', and I'll make that couple lines

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smaller. We want to import both 'COURSE', and this.

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We don't need to, we could actually just import this, and

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it'll work totally fine.

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But if we wanted to, we could import that variable as well.

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So let's go ahead and execute this.

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And so now we're importing a function that we made from

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'MyPackage.my_functions',

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and then we're also importing a function from a file called

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'subfolder_functions', a folder above that,

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the parent folder is 'MySubFolder', and the parent above

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that is 'MyPackage'.

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And when we run this, when we run this in Python, we'll see

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"This is from my_functions.py".

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And this one is, "The course is: Python for Everybody".

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And we actually don't have any 'print' statements in here whatsoever.

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And so we've now created what is effectively a package.

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Now to clarify how some of this is actually working,

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when you import from something you can say 'from MyPackage',

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and usually we name it

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whatever the regular package is called, it doesn't have to be

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uppercase or anything like that.

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Like we saw earlier that you could have 'from colorama import

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Fore', but the weird thing here is this '.' notation.

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So sort of what this is doing here is instead of for whatever

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reason, and I actually don't know this, but for whatever

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reason, we use dots instead of slashes.

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And so in Python, we can say 'from MyPackage' folder,

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look in 'MySubFolder' folder,

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and then the last one is likely to be a Python file, which

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you just automatically assume,

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so you don't have to write '.py',

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and instead we use this thing called '.' notation where folder

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name, folder name, file name, import your function.

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We could if we wanted to, do this a different way as well.

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We could say 'from MyPackage.MySubFolder import

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subfolder_functions', and then we could run 'subfolder_functions.

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which_course_is_this'

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And let's go ahead and execute this just to see that this is going to work.

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Now, I commented out both functions that we're running originally,

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so this one is not going to show up anymore.

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[no audio]

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And there it is. Just the one shows up, and we can even alias this if we

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want to. You might see this from time to time, because

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'subfolder_functions' is kind of a long name,

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so you might see something like this 'as', I don't know,

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'subfolder_functions', 'sff'.

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And then we can use that instead.

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And now this looks a lot like a class, doesn't it, where

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we have an object or a class name,

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and then we've got a method in it.

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And every now and then I mentioned that Python is, everything

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in Python is pretty much an object.

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Files are no different.

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And I do remember saying that. Files are no different in the

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sense that we imported this file, and now we have a function

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in here, and that's the method.

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Very interesting how they're very, very similar, isn't it?

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So just for funsies let's go ahead and run this, and it still works.

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[no audio]