NUMEROS = (("M", 1000), ("CM", 900), ("D", 500), ("CD", 400),
            ("C", 100), ("XC", 90), ("L", 50), ("XL", 40),
            ("X", 10), ("IX", 9), ("V", 5), ("IV", 4), ("I", 1))


def checkio(data):
    result = ""
    for roman, n in NUMEROS:
        if n <= data:
            result += roman * (data // n)
            data %= n
    return result

if __name__ == '__main__':
    #These "asserts" using only for self-checking and not necessary for auto-testing
    assert checkio(6) == 'VI', '6'
    assert checkio(76) == 'LXXVI', '76'
    assert checkio(499) == 'CDXCIX', '499'
    assert checkio(3888) == 'MMMDCCCLXXXVIII', '3888'