Roman to Arabic

[DyckBook]

I found this regex function on this forum and it worked at the time. Now it works the first time, and every time I open the edit function window, even without making changes, and thereafter returns 0. I'm not enough of a coder to know why. Could anyone please help?

The originally posted function had
n = unicode(n).upper(),
which I changed to
n = str(n).upper()
in order to make it work then. I understand that that was because of changes to Python. Could it be that Python has changed again?

numeral_map = zip(
    (1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1),
    ('M', 'CM', 'D', 'CD', 'C', 'XC', 'L', 'XL', 'X', 'IX', 'V', 'IV', 'I')
)
	   
def arabic_num(n):
    n = str(n).upper()
    i = result = 0
    for integer, numeral in numeral_map:
        while n[i:i + len(numeral)] == numeral:
            result += integer
            i += len(numeral)
    return result
def replace(match, number, file_name, metadata, dictionaries, data, functions, *args, **kwargs):
    return match.group(1)+str(arabic_num(match.group(2)))+match.group(3)

[DyckBook]

I found the answer to my question, thanks to AI.

The lines:
numeral_map = zip(
(1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1),
('M', 'CM', 'D', 'CD', 'C', 'XC', 'L', 'XL', 'X', 'IX', 'V', 'IV', 'I')
)

Needed to be replaced with this:

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

The function is working again and saving lots of fiddly work.