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→INVESTIGATION 4: USING PYTHON TO AUTOMATE MANAGING VIRTUAL MACHINES: - Re-writing instructions to be able to remove the bash scripting portion.
<li>Modify the if statement so it is just getting the current username, not the username and a newline. You can do this using several steps and several variables, but it can also be done in a single line.</li>
<li>Now that the script recognizes you as being root (or at least running the script with root permissions), it should work. Notice how we've used the + to combine several strings together to pass to the os.system command. We did this because this script needs the python variable to be evaluated before the whole line gets handed over to os.system. If you left the variable names inside the quotes, python will ignore them as just being part of a string. By putting them outside of a string, and concatenating their value to that string, we can evaluate them and feed them into that command.</li>
<li>Test your script to make sure it works. If it doesn't, go back and fix it. Do not continue until it successfully makes backups of your VMs.</li><li>There is a weakness to this script as written. Every time you run it, it will make a backup of all three VMs. But what if you only made a change to one of them? Do we really need to wait through a full backup cycle for two machines that didn''Convert t change? As the script is currently written, we do. But we can make it better.</li><li>Before the for loop that backs up each machine add a prompt to ask the rest of user if they want to back up all machines. Use an if statement to check if they said yes.<ul><li>if they did say yes, back up all the bash script above into pythonVMs using your existing for loop.</li><li>If they didn't say yes, then test do nothing for now.</li></ul></li><li>Test your python version script to make sure it works. Check what happens if you say 'yes'to the prompt, and check what happens if you say things other than 'yes'.</li><li>Now we have a script that asks the user if they want to back up all VMS, and if they say they do it does. But if they don't want to back up every VM, it currently does nothing.</li><li>Add an else statement to handle the user not wanting to back up every VM. Inside that else clause ask the user which VM they would like to back up (you can even give them the names of available VMs (Centos1, Centos2, Centos3).</li><li>Now nest and if statement inside that else so that your script can handle what your user just responded with. If they asked for Centos1, back up Centos1. If they want to back up Centos2, only back up Centos2, etc. Hint: You might want to use elif for this.</li><li>Test your script again. You should now have a script that:<ul><li>Makes sure the user is running the script with elevated permissions.</li><li>Asks the user if they want to back up every VM.</li><li>If they want to back up every VM, it backs up every VM.</li><li>If they user does not want to back up every VM, the script asks them which VM they do want to back up.</li><li>If they user selected a single VM, the script will back up that one VM.</li></ul></li>
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