Why doesnt my Python function print to console?

I can’t seem to figure out why my function doesn’t print anything when called.

This is the function (and a list that’s used in the function):

old_letters = ['a', 'p', 'c', 'f']

def try_update_letter_guessed(letter_guessed, old_letters_guessed):
    length = len(letter_guessed)
    english_validation = letter_guessed.isalpha()
    already_used = letter_guessed in old_letters_guessed

    if (length > 1) or (english_validation == False) or (already_used == True):
        print("X")
        delim = "->"
        res = delim.join(sorted(old_letters_guessed))
        print(res)
        return False
    elif (length == 1) and (english_validation == True) and (already_used == False):
        old_letters_guessed.append(letter_guessed)
        return True

However, when I call my function (with arguments) like so:
try_update_letter_guessed('A', old_letters)
it doesn’t print anything at all.
What am I missing?

>Solution :

When letter_guessed is 'A', then (length > 1) or (english_validation == False) or (already_used == True) is not true, so this goes to the elif, and that doesn’t print anything.

If you try with arguments which will make that condition true, then it does print:

>>> try_update_letter_guessed('AB', old_letters)
X
A->a->c->f->p
False
>>> try_update_letter_guessed('a', old_letters)
X
A->a->c->f->p
False