code: def romanise(number):
      
      if number is None:
          return ''
  
      roman_list = ['0', 'I', 'II', 'III', 'IV', 'V', 'VI', 'VII', 'VIII',
                    'IX', 'X', 'XI', 'XII']
      try:
          roman = roman_list[int(number)]
      except ValueError:
          return None
      return roman
docs: Return the roman numeral for a number.
  
      Note that this only works for number in interval range [0, 12] since at
      the moment we only use it on realtime earthquake to conver MMI value.
  
      :param number: The number that will be romanised
      :type number: float
  
      :return Roman numeral equivalent of the value
      :rtype: str