Small Error - Should be quick fix

I want to publish a anti suicide script.

hook.Add("CanPlayerSuicide", "antisuicide", function( ply )
		ply:PS_Notify("Suiciding is not allowed!")
   return false

However, I get this error

[ERROR] addons/errol's anti-suicide script/lua/autorun/server/antisuicide.lua:2: attempt to call method 'PS_Notify' (a nil value)
  1. fn - addons/errol's anti-suicide script/lua/autorun/server/antisuicide.lua:2
   2. unknown - addons/ulib2/lua/ulib/shared/hook.lua:183

Don’t know what I’m doing wrong, and can’t find a fix, all though it looks like a simple solution.
Any ideas?

Why are you using a Pointshop function?

AHH! Long story short, I took a line from pointshop to print text, how would I get the message to show as a hint, like when u start up gm_construct?

See if still works

EvacX, thank you, I really appreciate it, I used the bottom function and it worked : )