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So how do we go about blocking websites with Python?

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Windows, MAC or Linux

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they have a host file which is something like this.

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So this is the host file.

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And if you open the host file

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you'll see some lines there.

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And what this host file is for is that if you want to block certain web sites such as Facebook

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or this mail live here

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what you do is you tag them here as I have done here.

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I've typed them via Python

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in this case.

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But you can also type them manually

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in that case you don't  have control of the times when you want them to be here.

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So if you have a look at this, this is saying that

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the IP address should be placed in the first column followed by the corresponding hostname which means

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this is a redirect IP address.

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And this is a host name which underlies that if you want to block Facebook you want to redirect the browser

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to this IP address which is the local IP address of your computer which means when you try to access

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Facebook

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you'll be redirected to that IP that shows this error web page.

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Good.

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Now this hosts file

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on Windows it is located in this directory here.

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So Windows system 32 drivers.

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And then you have the host file which doesn't have an extension but you can open it as a text file

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in Atom or other text editors. On Linux or Mac that host file path would be something like

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this and host.

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So, very straight forward.

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This is both for Linux and Mac and on Windows

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that was this one here.

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So I'll copy that and just put it here.

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So that's for MAC and Linux and Windows.

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Good.

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Now that we know how this host file works

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we can open that as a file via Python

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using file handling methods and we can add lines of text at certain times of the day and

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this host file. For instance let's say I work between 8 a.m. and 4 p.m..

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In that case I'll write a Python script that runs the entire day and checks every let's say every

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five minutes it checks the time.

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And if it's past 4:00 p.m. then it will delete these two lines.

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But if you are between 08:00 and 16:00 Python on will add these two lines in this host file 

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and the host file

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will block access to these two websites. So that is starting to make sense I believe and all we need to start

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off is you have to think about let's say two websites that you want a block or more or just one.

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And also figure out where your host is located which I already showed to you.

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And yeah we should be good to go to start writing the program and we'll do that in the next lecture.

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