Npc Spawn Problem

[Abinox01]

Hello,
I have tryed to make an npc spawn script for my gamemode, it's look like this:
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function zombiespawn ()
local z=ents.Create ("npc_zombie")
z:SetPos( ZombSpawn )
z:Spawn()
z:SetColor(Color(255,0,0))
end

ZombSpawn = {}

ZombSpawn[1] = ( Vector (3664.375244, 2457.037354, 115.313522) )

timer.Simple ( "ZombieTimer", 20, 0, zombiespawn )
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but when i launch it, i have this message:
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[ERROR] gamemodes/0/gamemode/monster_spawn.lua:3: attempt to call field 'Create'
(a nil value)
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Can someone help?
Thank you.

[r0uge]

Please use

 tags for code else it is hard to read.

[editline]6th April 2015[/editline]

Where are you running this code?

[Abinox01]

In an lua file called zombie_spawn.lua in my gamemode folder

[CODE BLUE]

[QUOTE=Abinox01;47467788]In an lua file called zombie_spawn.lua in my gamemode folder[/QUOTE]

Are you running this server side. ents.Create can only be called serverside not clientside.

[Abinox01]

it's ok i find the problems thank you for your help