rot finder DGSE entry chalenge kek 2ez4me

DGSErot.lua

local str = "RH UNTR ONTUDY CDBGHEEQDQ BDBH, ZK JHMCH DRS EZHS ONTQ UNTR !"


local function ascii_base(s)
  return s:lower() == s and ('a'):byte() or ('A'):byte()
end
local function caesar_cipher(str, key)
  return (str:gsub('%a', function(s)
    local base = ascii_base(s)
    return string.char(((s:byte() - base + key) % 26) + base)
  end))
end
local function rot13_cipher(i)
  return caesar_cipher(str, i)
end

local function rot13_decipher(i) 
  return caesar_cipher(str, i) 
end
local function rot(i)
	print(i, rot13_cipher(i))
	print(-i, rot13_decipher(-i))
end
local i = 1;

while i < 13 do
	rot(i)
	i = i+1
end

lua -e "io.stdout:setvbuf 'no'" "DGSErot.lua"
lua: DGSErot.lua:10: attempt to perform arithmetic on global 'key' (a nil value)
stack traceback:
DGSErot.lua:10: in function DGSErot.lua:8
[C]: in function 'gsub'
DGSErot.lua:8: in function DGSErot.lua:7
(tail call): ?
DGSErot.lua:21: in function 'rot'
DGSErot.lua:27: in main chunk
[C]: ?

can you help me?

Fixed it