Allow Redefinitions of For Loop Iteration Variables

Bug Report

MyPy has a flag --allow-redefinition to enable variable redefinition in limited circumstances. This doesn't seem to work with variables bound in a for loop iteration.

To Reproduce

https://mypy-play.net/?mypy=1.5.1&python=3.11&flags=allow-redefinition&gist=005972804edd5316ace18ea835fb9f52

for i in range(3):
    i: str = str(i)
    reveal_type(i)
    
def test(i: int):
    i: str = str(i)
    reveal_type(i)

Expected Behavior

Both cases are allowed.

Actual Behavior

MyPy throws an error only for line 2.

main.py:2: error: Name "i" already defined on line 1  [no-redef]
main.py:3: note: Revealed type is "builtins.int"
main.py:7: note: Revealed type is "builtins.str"
Found 1 error in 1 file (checked 1 source file)

Your Environment

MyPy Version v1.5.1

Inizia eseguendo la riproduzione collegata di mypy-play con MyPy 1.5.1, l’esempio Python 3.11 e --allow-redefinition. Traccia come vengono gestiti la variabile del ciclo for e il parametro della funzione, quindi aggiungi una copertura che mostri che entrambe le ridefinizioni sono accettate e che i tipi rivelati corrispondono all’output previsto.