base64

注意：base 64 编码的作用是将 字节 处理成 b64 的组成！

import base64  

s = "abc"  
bs = s.encode("utf-8")  
bs64 = base64.b64encode(bs)  

print(bs)  
print(bs64)  
print(bs64.decode())  

s = "YWJj"  
print(base64.b64decode(s.encode("utf-8")).decode())

使用场景：

print(base64.b64encode("我想去长沙，你也陪我去，好吗".encode("utf-8")).decode().replace("+", "-"))  

print("5oiR5oOz5Y676ZW/5rKZ77yM5L2g5Lmf6Zmq5oiR5Y6777yM5aW95ZCX".__len__()/4)