bat批处理文件，语法错误在哪？

Question

@echo off
echo %l%
cd d:/aaa/py3
if exist %l% (
title %l%
python %l%
echo %errorlevel%
)
else (
echo "文件不存在"
Rem exit
pause
)
pause

bat批处理文件，语法错误在哪？