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As you were able to see in the previous lectures our script is now running very smoothly.

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So what's left to be done there is to make this script run on the background as soon as the computer starts.

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Which means that the python program, the script that we built will run  and it will check for the time and

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then it will do something depending on what time it is.

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But at the moment the way we are running this is by opening a command line and then pointing to the

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script and that command line remains open as the script is runing.

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So probably we don't want that, we don't want to have the terminal open there all the time as we do work

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in our computer.

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So a better solution would be to find a way to run the script on the background and there exists a solution.

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It's just that the workaround is different on Windows and on a Mac and Linux.

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So this lecture is about making the final touch to the program so that we can make it work on Windows

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to have a Python program we're on as a process in the background.

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So Linux users and Mac users can safely skip this lecture and go to the next one where you can

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implement these scripts as a background process.

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So yeah, hello Windows user.

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I'm on Windows 7 here but the solution should work on other versions of Windows as well.

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So how do we make a script for on a in the background a process?

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Well there's a simple trick you can do on Windows.

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You know you have a selection of Python there that you open for location.

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So when you were runing a program when you say Python script.py you are using this python.exe

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file

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which is the executable of the python program. Use this program to run your file. Now to run python

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files on the background you want to use Pythonw.exe which is specific subversion or Python

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for running Python scripts as a background and there is a simple trick you can do.

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You want to change the extension to pyw and once you do that

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now you can go ahead.

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So here is the file which extension

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I just change and what you can do now is just the double click this to execute it and there is no terminal

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showing.

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So the script should be running now and you can verify that in that task manager.

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So this one here which you can open by the way right click in here and or Start Task Manager and then

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go to processes and there you should be looking for python, for a process named Python here.

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And this time I expect this not to be here.

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So Python is not here so you should expect Pythonw.exe to be here.

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And the reason it is not there is that the script wasn't able to run because when you double click this

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you are double clicking you as a user not as an administrator.

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And if you're not executing it as an administrator you are not being able to access this to modify this

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hosts file because as you know from the previous lectures this is a protected file by Windows.

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But if you change these hosts file, let's change it to the hosts temp which is this local file here.

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So a fake hosts file.

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Well we don't need administrator rights to access it. Hosts temp.

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And now I go ahead and double click the Python file again.

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And now I should see Pythonw.exe in the processes as you see here.

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So you don't really see any output printed out but you can see maybe the results of this.

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So this is the hosts file which hasn't been added the domains in here because this says

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the working hours or between four and seven pm.

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Now it's 02:38.

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So let's change this to eight and 16.

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Save the script and go and stop this process because this is running 

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the old file and process and now run again the file and check the hosts file and now you should see these four

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lines which have been added in here.

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Great.

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Now let me stop this and process.

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And yeah, we are able to run our Python file as a process in the background.

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Now let's go ahead and implement the scheduling part.

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So we want to run this program as soon as the computer starts. To do that

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you want to go to task scheduler just there.

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And then create a base, create a task. Put a name for the task.

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I'm calling this a Website Blocker and configure for�

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I'm on a Windows 7.

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So I'm going to choose that.

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So Windows 7.

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And one important thing to do is you want to check this run with highest  privileges because if you don't

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do that, Windows will try to run the script from the normal user so you won't�

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In our case we need administrative rights.

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So check that and then go to Triggers and then New. So begin the task.

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When do you want to run the program.

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Well we want to run the program at startup.

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It should be fine.

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Then go to actions and you want to create a new action.

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So what you want to do well we want to start a program and normally want to point to your program script

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which is this one here.

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Website blocker.pyw. Open that. OK conditions.

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And you may want to uncheck this option.

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You also want to run the python program when you're on a battery on a laptop.

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And yeah, we should be good to go now.

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Press

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OK.

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and

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here is the Website Blocker task which is ready to be run when the system starts up.

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So you may also want to disable it but that's for another case.

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And yeah, now when you start your computer the program should be running. Your Python loop will run

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every five seconds.

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The Python program will check of the hosts file and so on and so you may want to test to start to

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restart your program.

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Or you can go here and test it by clicking Run. Now the status is showing is running.

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And you may want to check if the task is really running or not.

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And it seems like it's not runing.

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So python.exe is not here.

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And the worst thing is that we don't even get any error now because the task, the Python process

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is running on the background and I know the reason why it's not running.

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You know if you see in the script now you notice that I'm still trying to modify the local hosts file who's

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path is being passed in here as a relative path.

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So this is not an absolute path like this one here.

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The problem with that is you know Windows is now executing this website blocker.pyw

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script is executing it from another directory.

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So it's not executing this from D Dropbox pp block website demo.

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Therefore it cannot find a file with this path.

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Therefore the solution to these is to actually pass the full path of the file here.

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Because as we are now Python is not trying to find the hosts file.

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So it's probably throwing an error that says the host file does not exist.

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So let's go ahead and copy this directory put it there.

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And of hosts. A backslash there and pass R prefix so that you can escape special characters.

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Save that.

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And yeah, now go to the task scheduler and this. Try to run again.

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So I'd say so running now. Let's see and yeah now this is running.

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So Pythonw.exe and you can also check the hosts file.

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So the lines are there because it's between 8:00 and 4:00 pm.

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So it's four to three the time.

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And yeah, the final thing we want to do is stop this very quickly.

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And change this to the real path. Hosts path. And this as well.

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Save it and go to the task scheduler.

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And add the current task.

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So it's ready now and runs again.

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Go to the processes. Pythonw.exe is there.

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So it's running.

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You may also want to check the horse fall which is in my notepad which says

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the file has been modified.

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Yeah I can see the lines there.

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The four websites that I want to block and maybe you are wondering why this first line is there.

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It should be separated in here and be there but the reason this line was up here was because the cursor

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was set to these point before executing the Python script.

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So you may want to set the cursor.

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Let me delete this.

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You may want to set the cursor in here before starting the python program.

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So before implementing this program.

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Now I saved it and I now expect this file to be refreshed by Python again.

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So let me close that and open it again.

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And now yeah, now this looks good.

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We have an empty linr there but that isn't a problem.

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So things will still work even with Facebook in here like it was earlier.

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Things should also work and everything looks to be working fine.

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I now cannot access Facebook.

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Between 8:00 a.m. and 4:00 p.m. and that's all about it.

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In the next lecture 

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I'm showing how to do the same.

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So how to run Python as a processes in the background for Linux and Mac users and that will end this section.

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So hope you enjoyed it and I hope you make the most of this program for you or use your daily use.

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If something isn't working just drop me a question or a message and yeah I'll be happy to help you.

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Or even if you have questions regarding the script so I know this has been lots of indentation here.

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Probably you'll get some errors there and probably that error is because of indentation so be careful with indenting

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your lines.

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And yeah, I'll close this now and I'll see you in the next lectures.

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Thanks.