$ python3 -m bottle_encoding.py
Bottle v0.12.13 server starting up (using WSGIRefServer())...
Listening on http://localhost:8080/
Hit Ctrl-C to quit.

127.0.0.1 - - [09/Jun/2018 20:25:07] "GET / HTTP/1.1" 200 167
127.0.0.1 - - [09/Jun/2018 20:25:10] "GET /utf HTTP/1.1" 200 30
127.0.0.1 - - [09/Jun/2018 20:25:14] "GET /latin1 HTTP/1.1" 200 30
127.0.0.1 - - [09/Jun/2018 20:25:16] "GET /iso88591 HTTP/1.1" 200 30

----------
RESULT
link1: {"b": "\u017d", "a": "\u4e09"}
link2: {"b": "\u017d", "a": "\u4e09"}
link3: {"b": "\u017d", "a": "\u4e09"}