code: def mod9710(iban):
      
      remainder = iban
      block = None
  
      while len(remainder) > 2:
          block = remainder[:9]
          remainder = str(int(block) % 97) + remainder[len(block):]
  
      return int(remainder) % 97
docs: Calculates the MOD 97 10 of the passed IBAN as specified in ISO7064.
  
      @method mod9710
      @param {String} iban
      @returns {Number}