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)