为什么str无法在python中将对象转换为字符串？

Question

/home/user/reverse.py的内容：

#!/usr/bin/environment python2.7

def reverse(string):
    print("reversed: "+string[::-1])

name=str(input("Key in String to Reverse:"))
reverse(name)

$python /home/user/reverse.py
Key in String to Reverse:abcdef

执行错误时：

name abcdef is not defined.

请帮助我解决问题！