写一个数学类，实现两个数之间的加减乘除

class Number:
    def __init__(self,num1,num2):
        self.num1 = num1
        self.num2 = num2
    def add(self):
        return self.num1+self.num2
    def sub(self):
        return self.num1 - self.num2
    def ride(self):
        return self.num1 * self.num2
    def div(self):
        if not self.num2 == 0:
            return self.num1 / self.num2
# n = Number(3,4)
# result = n.ride()
# print(result)

    @classmethod
    def pingfanghe(cls,num1,num2):
        n1 = cls(num1,num1)
        n11 = n1.ride()
        n2 = cls(num2,num2)
        n22 = n2.ride()

        n3 = cls(n11,n22)
        return n3.add()
result = Number.pingfanghe(4,6)
print(result)