import uuid


def points_to_mark(good, total):
    percents = good / total * 100
    if percents < 50:
        return 2
    elif percents < 66:
        return 3
    elif percents < 90:
        return 4
    else:
        return 5


def answer_letter(answer, variants):
    answer = answer.lower()
    for var in variants:
        letter, var = var.split(') ')
        if var == answer:
            return letter + ') ' + answer


def is_valid_uuid(value):
    try:
        uuid.UUID(str(value))
        return True
    except ValueError:
        return False