刚刚自学lua脚本 请问这是我语法问题吗

问题遇到的现象和发生背景

问题相关代码，请勿粘贴截图

EnablePrimaryMouseButtonEvents(true);
function OnEvent(event, arg)
https://img-mid.csdnimg.cn/release/static/image/mid/ask/111553950946162.png "#left")
--OutputLogMessage("Event: "..event.." Arg: "..arg.."\n")
if arg == 1 then
while (IsMouseButtonPressed(3)) do
MoveMouseRelative(-3, 4)
Sleep(3)
MoveMouseRelative(3, -2)
Sleep(3)
MoveMouseRelative(-3, 1)
Sleep(3)
MoveMouseRelative(3, -1)
else AbortMacro(1)
end
end
end

运行结果及报错内容

else 那里出错

我的解答思路和尝试过的方法

我想要达到的结果

我想按住左键时启动 松开左键后停止

EnablePrimaryMouseButtonEvents(true);
function OnEvent(event, arg)
--OutputLogMessage("Event: "..event.." Arg: "..arg.."\n")
if arg == 1 then
while (IsMouseButtonPressed(3)) do
MoveMouseRelative(-3, 4)
Sleep(3)
MoveMouseRelative(3, -2)
Sleep(3)
MoveMouseRelative(-3, 1)
Sleep(3)
MoveMouseRelative(3, -1)
else AbortMacro(1)
end
end