new_contents: from collections import OrderedDict
  ​
  def checkio(num):
  ​
      roman = OrderedDict()
      roman[1000] = "M"
      roman[900] = "CM"
      roman[500] = "D"
      roman[400] = "CD"
      roman[100] = "C"
      roman[90] = "XC"
      roman[50] = "L"
      roman[40] = "XL"
      roman[10] = "X"
      roman[9] = "IX"
      roman[5] = "V"
      roman[4] = "IV"
      roman[1] = "I"
  ​
      def roman_num(num):
          for r in roman.keys():
              x, y = divmod(num, r)
              yield roman[r] * x
              num -= (r * x)
              if num > 0:
                  roman_num(num)
              else:
                  break
  ​
      return "".join([a for a in roman_num(num)])
  ​
  
subject: Update roman_numerals.py