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Hey, welcome back.

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This video is one of those videos where we don't improve the program output, but we improve the code.

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What do we mean by that?

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We will make the code more readable, more efficient.

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So nothing on the output will change.

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What we will do exactly is we're going to use a better way to handle the files.

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So, for example, here we are opening a file in read mode than we read the lines of that text file.

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We store the lines in the lists and then we close the file.

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But this can be done in a better way using the with context manager.

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So from this we're going to use with.

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And here we place.

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This function.

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So I copy that.

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I place it in here and then this variable will go at the end using the SE.

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Key words as file.

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And then you use a column which denotes that the next line will be indented.

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So this is indented under this width.

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BLOCK So this is a block, and everything that goes underneath it is indented.

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So now what do we want to do now?

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Well, perhaps we want to read lines from that file.

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So whatever you want to do with that file, you want to write it here.

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In our case, it is to do equal to file that read lines.

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So this one, I'll just copy and paste it here and that's it.

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You don't need to close the file, and that is the benefit of this.

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With context manager.

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So I'll delete that line.

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And if you run the code now, you're going to get the same exact output.

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So nothing will change.

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So this method also makes sure to avoid some problems with file handling, for example.

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What will happen here is that.

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The file is open.

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And then even if the the program stops for some problems.

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The file will be closed by this method.

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But in the other case where we had this file equal to open file write lines.

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If the program stops at this point, then the next line will not be executed.

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So file that closed will not be executed, and we will end up with an open file which could cause problems.

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So this method, this block of code makes sure that that will not happen.

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So this is always recommended over this.

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Of course, first I wanted to show you this because you understand the logic better, but then we want

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to change that.

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So let's change this other block of code to a with context manager.

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It to be with.

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That's as file.

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And then that goes in here and that's it.

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So delete that.

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The code also becomes a bit shorter, as you can see.

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Let's do the same in here with.

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That as file.

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Do that and delete that.

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And that's what we have.

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So let me test this.

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If everything is working fine, so show that we will show what we have so far.

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Add a new to do, right, for example.

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That's a new to do that I've just added show right.

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Is part of the to do list.

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So everything is working fine.

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So we just modified the show, the ADD case and also the showcase.

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Now, we still haven't implemented the changes in the edit and the complete cases, so these are still

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not connected to our text file.

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They are not connected to our actual data, but we will do this in the next video.

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So I'll see you there.