Manually set button to turn off your display in Ubuntu 17 (with just one command)?

Hi,
I am a Ubuntu user and I had option on my keyboard to turn off display with just pressing a combination of key on your keyboard but sadly for windows it for. So i found a solution to problem.

Here follow me:
(Check this command first in terminal, it should turn off your screen until you press any button)
Shortcut to open terminal : Ctrl + Alt + T

Command :  xset dpms force off

If this work successful then follow these 2 simple steps: 

Step 1: Go to Settings > Devices > Keyboard > + (Scroll down to last your will see)

Step 2: Now it will ask Name your shortcut , command, Shortcut key

Name: Turn off screen MANUALLY (Fill whatever you better remember)

Command: xset dpms force off

Shortcut key: Press shorcut key you want to set 

And you are all set! Now try and enjoy!