http://www.checkio.org/mission/task/roman-numerals/

roman-numerals.py

def checkio(n):
    'return roman numeral using the specified integer value from range 1...3999'

    if 1 <= n <= 3999:
    	return ''.join(to_roman(n))

 
def to_roman(num):

    roman = [["","I","II","III","IV","V","VI","VII","VIII","IX"],
          ["","X","XX","XXX","XL","L","LX","LXX","LXXX","XC"],
          ["","C","CC","CCC","CD","D","DC","DCC","DCCC","CM"],
          ["","M","MM","MMM"]]
    
    i= 10000
    out = []
    for j in range(4):
        n = (num%i) / (i/10)
        i/=10
        if roman[3-j][n]: 
        	   out.append(roman[3-j][n])
    return out
    

 

if __name__ == '__main__':
    assert checkio(6) == 'VI', 'First'
    assert checkio(76) == 'LXXVI', 'Second'
    assert checkio(499) == 'CDXCIX', 'Third'
    assert checkio(3888) == 'MMMDCCCLXXXVIII', 'Fourth'
    print 'All ok'