code: def __set_amount(self, value):
          '''
          Sets the amount of the payment operation.
          @param value:float
          '''
          try:
              self.__amount = quantize(Decimal(str(value)))
          except:
              raise ValueError('Invalid amount value'f __set_amount(self, value):
          '''
          Sets the amount of the payment operation.
          @param value:float
          '''
          try:
              self.__amount = quantize(Decimal(str(value)))
          except:
              raise ValueError('Invalid amount value')
docs: Sets the amount of the payment operation.
          @param value:float