想做一个便捷的过滤器函数，为什么报错啊，大佬help

Traceback (most recent call last):
File "<pyshell#0>", line 1, in <module>
maxapiltconction("return args*2",0,[1,54,364,34])
File "D:\马Horse\python\Lib\info.py", line 625, in maxapiltconction
print(list(map(conc,lst)))
File "D:\马Horse\python\Lib\info.py", line 622, in conc
exec(returncode)
File "<string>", line 1
SyntaxError: 'return' outside function