linux — display off / prevent display off

I keep my laptop on most of (all) the time. To turn the display off when I sleep etc. I have the following alias in my ~/.bashrc

alias doff=’sleep 5; xset dpms force off’

doff command then gives me enough time to ctrl+alt+L before the display switches off.

To prevent turning off the display / screen blanking etc. while the system is idle and I am thinking / watching movies etc. I have the following alias

alias don=’xset -dpms; xset s off’

I did not invent these by any means, to know more — link