python str与bytes之间的转换

 # 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)