def get_nth_last_vowel(phones, n):
    """
    Given the rhyme level  n and a syllable (phone) list, count backward witin the list to find the nth vowel.
    Return the (negative) index where it can be located.
    """

    vowel_count = 0
    for i in range(1, len(phones) + 1):
        if phones[-i][-1].isdigit():
            vowel_count += 1
            if vowel_count == n:
                return -i