I've found a method to program Core S3 using Python.
I'm interested in getting feedback if anyone has a better method.

1. Install UIFlow2.0 using m5Burner
2. Go to uiflow2.m5stack.com
3. Click on the python tab, </>
4. Click on Read Mode
5. Edit your Python code
6. Click on "Download the program to device"
7. It will start automatically.
8. Repeat from 5 until you programming is done.

If you click on "Read Mode"/"Custom Edit", you will lose your code changes.
I have NOT found a method of transfering files instead, so I am using Copy & Paste at the moment.

I did NOT find any debugger so I'm using print() instead.

Not much documentation online, but UIFlow creates Python code, which you can simplify and reuse.

You need to check these links: MicroPython and Core S3