It is not a game script, just a script I quickly wrote to demonstrate the GrantSpell function and show the documentation for it in the scripting tool, that can be found manually in the nwscript.nss file if you need to find it.
But in general you can just type out a function and hit enter and it will be displayed at the bottom, or you can navigate the functions down the right side of the program and click them to have the relevant notes displayed at the bottom of the application.