spawner func

function spawn(x,y,z,entid)
-- Create a spawner
w.setBlock(x, y, z, 52, 0)

-- Get an NBT table representing the tags of the spawner
local te = w.getTileEntity(x, y, z)
local nbt = readTileNBT(te)

-- Add the entity id
table.insert(nbt.value.EntityId,{type="short",value=entid})

-- Write to world
writeTileNBT(te, nbt)
end