This script opens a new iTerm tab at your currently active Finder window's directory. It opens a new iTerm window there instead if you don't have iTerm running yet.
Referenced from the original tutorial written by Peter Downs at http://www.jofu.org/blog/2016/02/04/open-iterm-tab-from-finder-by-shortcut.
You just want a short script with minimal configuration to get this shortcut working. For a more fully-featured solution, please use "iTerm2 Finder Tools" which you can download from Peter Down's GitHub repository.