Want to include Japanese in communication content

Hello to the community!
I’m a Japanese hobbyist and smart home builder.

I had an opportunity to get a F401RE and decided to use it to do some Python programming. So, I started programming with Zerynth Studio, referring to this article. After I succeeded in “Blink”, I tried to do this and that using serial communication, but I had trouble using Japanese.

I tried the following code, but it outputs ?????????????????????????? in the output. I also tried giving # -*- coding: utf-8 -*-, a common solution, but it didn’t work.

import streams
s=streams.serial()

while True:
    print("シリアルポートに文字を書き込んで、\\n(改行)で終了")
    line=s.readline()
    print("You wrote:", line)
    print()
    sleep (300)

In addition, when I try to use Japanese in the console input, I get the error 'utf-8' codec can't encode character '\udc82' in position 0: surrogates not allowed.
In this example, I entered and あああ.
To deal with this, I looked at this article and added a “spell” to it.

But I got the following error.
[error] Can't find module [sys] imported by [D:\document\#Worktable#\#Programming#\Dev_and_WiP\Zerynth_Blink\Serial_Port_Read-'

I’ve looked up [“Zerynth Studio” “import sys”] etc. but can’t find any information. Can you please share your wisdom with me?