$ cat ruf052.py
def f(_x):
    return _x
print(f(_x=1))

$ python ruf052.py
1

$ ruff check --isolated --preview --select RUF052 ruf052.py --fix
Found 1 error (1 fixed, 0 remaining).

$ cat ruf052.py
def f(x):
    return x
print(f(_x=1))

$ python ruf052.py
Traceback (most recent call last):
  File "ruf052.py", line 3, in <module>
    print(f(_x=1))
          ^^^^^^^
TypeError: f() got an unexpected keyword argument '_x'