class TomatoPrice:
    price: float

    def __init__(self, value):
        self.price = value

    def __str__(self):
        return f"USD${self.price}"

    def __radd__(self, operand):
        self.price += operand.price

vietnam = TomatoPrice(3.0)
japan = TomatoPrice(4.0)
korea = TomatoPrice(5.0)

vietnam + japan

output = "price of tomatoes in countries A, B, C: " + str(vietnam) + " " + str(japan) + " " + str(korea) + " "
print(output)