OT: How to add a menu item to system wide context menu (KDE)

Hi all,

does anybody happen to know if it’s possible to add an option to the system wide context menu in KDE (Centos 7)? Kinda like you can in OSX by adding a service?
I’d like to be able to select text in, say, Google Hangouts, and fire off a custom python command with it.
Any pointers would be greatly appreciated!