Python类的方法实现复数四则运算

问题遇到的现象和发生背景

用Python类的方法实现复数四则运算

问题相关代码，请勿粘贴截图

class Complex:
    def __init__(self, x, y):
        self.x = x
        self.y = y

    def __add__(self, other):
        return Complex(self.x + other.x, self.y + other.y)

    def __sub__(self, other):
        return Complex(self.x - other.x, self.y - other.y)

    def __mul__(self, other):
        return Complex(self.x * other.x - self.y * other.y, other.x * self.y + self.x * other.y)

    def __truediv__(self, other):
        return Complex((self.x * other.x + self.y * other.y) / (other.x * other.x + other.y * other.y),
                       (other.x * self.y - self.x * other.y) / (other.x * other.x + other.y * other.y)

    def __str__(self):
        return "%d + %di" % (self.x, self.y)


c1 = Complex(2, 4)
c2 = Complex(3, 1)
c3 = c1 + c2
c4 = c1 - c2
c5 = c1 * c2
c6 = c1 / c2
print(c3)
print(c4)
print(c5)
print(c6)

运行结果及报错内容

  File "C:/Users/hp/PycharmProjects/lesson/practice.py", line 139
    def __str__(self):
      ^
SyntaxError: invalid syntax

我的解答思路和尝试过的方法

之前编辑的确实是少了括号，改过后这里却还有问题

我想要达到的结果

可以解释一下吗谢谢

最后一个函数的括号缺失，试试这样：

    def __truediv__(self, other):
        return Complex((self.x * other.x + self.y * other.y) / (other.x * other.x + other.y * other.y),
                       (other.x * self.y - self.x * other.y) / (other.x * other.x + other.y * other.y))