Let me know what kind of "feature" you have in mind — encode, decode, validate, generate, or integrate into a specific system (Python, JavaScript, game, etc.) — and I’ll write the exact code or logic for you.
If it's :
Last 9 stays 9 .
"thmyl wyb brw 9"
thmyl → guzly wyb → jlo brw → oej
Could you clarify what you mean by this? thmyl wyb brw 9