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All right. So let's begin.

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And the very first thing we're going to do

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is we're going to import the required library.

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And that's of course, going to be the Cryptography dot fernet.

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So

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I'm gonna come in here and say from

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and then Cryptography

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does fnet now import

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fernet.

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OK.

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Now we want to write a function

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that we can use to generate and save our encryption key.

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So let's go ahead and create a function.

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I'm going to call this one define and let's say generate

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underscore key.

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And now in brackets.

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So this is gonna be the name of our function,

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which we're going to use to generate our encryption key.

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Now, the thing is whenever you're generating your keys,

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whenever you're using this function,

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we can actually add a particular kind of parameter

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which will be the file path, we can create the name of our file.

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So what I'm gonna do right now is I'm gonna say file

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and now underscore path,

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OK, will now be equal. And now we can add the name of the file in

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this case right now in codes, I'm going to say encryption

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underscore key

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dot key.

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So this is how you want to save the file for your encryption key.

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It's going to be the name and then dot key and I'm going to add my colon at the end, very,

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very important.

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So now to generate the actual key itself, you can see

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it's already given us the

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information I'm gonna say key

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equals and now fer

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A F

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and now dot

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generate

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underscore key and now in brackets. So

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this right here is what we're going to use to generate the actual key.

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We're going to use this method which is the fer

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to generate key

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and we're going to save it in a variable called key.

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So now let us create the actual file itself. So

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I'm gonna come in here right now

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and I'm gonna say with OK

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with

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and now open. So we're gonna create our file and now in brackets,

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I'm going to add the file path.

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OK? And now comma

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and now

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the right mode. So it's gonna be WB

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and now I'm gonna say

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key

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on the score file.

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So this right here will open up a file in what we call a right binary mode.

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Now, you may wonder what exactly is WB,

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it's similar to the right mode which will

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just be w which we're already familiar with.

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However,

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in WB, you will write data in a binary format

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instead of plain text. So basically this means it will write data as raw bytes

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rather than characters. Now you might be wondering. OK.

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So what exactly is the point? What is the advantage? Well,

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if you write binary

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data using your regular text mode, which will be w

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the program will attempt to interpret the bytes

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as characters which can very often result in

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encoding errors, data corruption,

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or maybe even loss of data integrity. So

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using WB is always recommended whenever you're working with encryption,

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image files or any non text data to ensure that

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the data will be correctly stored in its original byte format

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without any alteration.

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All right. So now we'll have to write the key to the file.

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So I'm going to come over here right now

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and I'm gonna say key

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underscore file and now the method writes

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and now what are we passing in? We're passing in the actual key itself.

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So this right here will write the key to the file

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and then it's done, but we can also just write something to print out.

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So let's just say

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print.

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OK. And now in brackets,

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we can use our string

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and I'm gonna say codes, let's say encryption

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encryption key saved

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two.

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And now we can add the file path

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underscore path

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and there it is. So

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we have successfully created the function for generating our encryption key.

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But now we'll also write another function to load the encryption key from the file.

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So

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I'm going to come in here,

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I'm going to say, define load underscore key.

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And now in brackets, I'm going to add our file path

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and now this will be equal of course to encryption key,

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encryption underscore key key.

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So now from here

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I'm going to say

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uh with

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and now open

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can I add the file on the score path?

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And now we want to read, right? We want to read from the file.

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So what do you think we're going to use, we're going to use RB

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as opposed to WB. So

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it's not going to be in codes,

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it's going to be RB.

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Let me add my comma

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right there

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and then close the bracket. And now as key

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underscore file,

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add a colon.

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And now finally to with the key from the file, we can simply say key equals

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and then key

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underscore file dot the

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read method

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and now in brackets

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and now we can simply return

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our

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key.

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So the function we've just created right here,

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the load underscore key will simply read and

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return the decryption key stored in the file.

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And of course,

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this is going to be the key that will be needed for both encryption and decryption.

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So join me next video where we're going to go ahead right now

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to write functions to encrypt a file and also to decrypt the file.