Is there still a command like exec but for lua files?

I remember back in Garry’s Mod 12 there was this command I used which was sort of like exec (would execute a .cfg file in the cfg directory). I’ve tried looking for things like lua_exec, exec_lua, l_exec, and lexec but none of these are apparently it. I recall using this command and it was extremely helpful.

I looked on the Garry’s Mod wiki but I didn’t find anything.

lua_openscript and lua_openscript_cl

Thanks, also apparently the script I’m using was broke during Garry’s Mod 12 -> 13. Is there a changelog directory I can access so that I may repair it?