В строке записано десятичное число. Записать данное число римскими цифрами

def checkio(data):
    ones = ["", "I", "II", "III", "IV", "V", "VI", "VII", "VIII", "IX"]
    tens = ["", "X", "XX", "XXX", "XL", "L", "LX", "LXX", "LXXX", "XC"]
    hunds = ["", "C", "CC", "CCC", "CD", "D", "DC", "DCC", "DCCC", "CM"]
    thous = ["", "M", "MM", "MMM", "MMMM"]
 
    t = thous[data // 1000]
    h = hunds[data // 100 % 10]
    te = tens[data // 10 % 10]
    o = ones[data % 10]
 
    result = t + h + te + o
    print(result)
    return result
 
data = int(input())
checkio(data)
 
>>>2345
>>>MMCCCXLV

TEMPLATE = ['d', 'dd', 'ddd', 'dm', 'm', 'md', 'mdd', 'mddd', 'du', 'u']
RANKS = {1: ['I', 'V', 'X'], 2: ['X', 'L', 'C'], 3: ['C', 'D', 'M'], 4: ['M', 'W', 'Y']}
 
 
def to_roman(value: int) -> str:
    if value > 3999 or value < 1:
        raise ValueError(f'Only integers allowed form 1 to 3999, but got {value}')
    str_value = str(value)
    result = ''
    for index, num in enumerate(str_value):
        if num == '0':
            continue
        rank = len(str_value) - index
        down, middle, up = RANKS[rank]
        result += TEMPLATE[int(num) - 1].replace('d', down).replace('m', middle).replace('u', up)
    return result
 
 
assert to_roman(1) == 'I'
assert to_roman(8) == 'VIII'
assert to_roman(12) == 'XII'
assert to_roman(43) == 'XLIII'
assert to_roman(139) == 'CXXXIX'
assert to_roman(850) == 'DCCCL'
assert to_roman(1000) == 'M'
assert to_roman(900) == 'CM'
assert to_roman(3999) == 'MMMCMXCIX'