往往python2能运行，到python3就会报这个错误，这是编解码时的问题，python3是bytes-like。在进行字符串操作时，我们只需要转换一下就可以了。
# bytes object
b = b"example"
# str object
s = "example"
# str to bytes
bytes(s, encoding = "utf8")
# bytes to str
str(b, encoding = "utf-8")
# an alternative method
# str to bytes
str.encode(s)
# bytes to str
bytes.decode(b)
参考文章：https://blog.csdn.net/csu_vc/article/details/78372932