treat uppercase variables as `Final`

[scarf005]

Feature

A = 1
A = 2

make A be treated as

from typing import Final


A: Final = 1
A = 2

thus, it will emit error with

test.py:1: error: Cannot assign to final name "A" (because it is uppercase)
Found 1 error in 1 file (checked 1 source file)

Pitch
It would be convenient to not add Final to uppercase variables.
Since pep 8 states that constants are named with uppercase, uppercase variables could be considered Final.

Pylance also uses this convention and warns when UPPERCASE variables are mutated.