code: def investment_term(self, investment_term):
          
          try:
              if isinstance(investment_term, (str, int)):
                  self._investment_term = int(investment_term)
          except Exception:
              raise ValueError('invalid input of investment type %s, cannot be converted to an int' %
                               investment_term)
docs: This investment term is in months.  This might change to a relative delta.