编写python程序，实现一个复数类，要求是支持复数的加减乘除和指数运算，支持求模，求相角，支持复数的打印输出。对设计的复数类进行测试。（测试用例自己定）。

为了编写一个复数类，我们可以定义一个名为`ComplexNumber`的类，包含实部和虚部属性，以及相应的运算方法。下面是简单的实现：

import math

class ComplexNumber:
    def __init__(self, real=0, imag=0):
        self.real = real
        self.imag = imag

    # 加法
    def __add__(self, other):
        return ComplexNumber(self.real + other.real, self.imag + other.imag)

    # 减法
    def __sub__(self, other):
        return ComplexNumber(self.real - other.real, self.imag - other.imag)

    # 乘法
    def __mul__(self, other):
        real_part = self.real * other.real - self.imag * other.imag
        imag_part = self.real * other.imag + self.imag * other.real
        return ComplexNumber(real_part, imag_part)

    # 除法
    def __truediv__(self, other):
        denominator = other.real**2 + other.imag**2
        if denominator == 0:
            raise ZeroDivisionError("Cannot divide by zero")
        real_part = (self.real * other.real + self.imag * other.imag) / denominator
        imag_part = (self.imag * other.real - self.real * other.imag) / denominator
        return ComplexNumber(real_part, imag_part)

    # 指数运算
    def __pow__(self, power):
        if isinstance(power, complex):
            return pow(self, power.real) * pow(complex(1, power.imag), power.imag)
        else:
            return math.exp(power * math.log(self))

    # 求模
    def modulus(self):
        return (self.real**2 + self.imag**2)**0.5

    # 求相角
    @staticmethod
    def phase(angle):
        angle_rad = math.radians(angle)
        return ComplexNumber(math.cos(angle_rad), math.sin(angle_rad))

    # 打印输出
    def __str__(self):
        return f"{self.real} + {self.imag}i"

# 测试用例
test_cases = [
    (ComplexNumber(1, 2), ComplexNumber(3, 4), ComplexNumber(4, 6)),
    (ComplexNumber(2, 0), ComplexNumber(-2, 0), ComplexNumber(0, 0)),
    (ComplexNumber(1, 1), ComplexNumber(1, 1), ComplexNumber(0, 0)),
]

for case in test_cases:
    result = case[0] + case[1]
    print(f"Addition: {case[0]} + {case[1]} = {result}")

    result = case[0] - case[1]
    print(f"Subtraction: {case[0]} - {case[1]} = {result}")

    result = case[0] * case[1]
    print(f"Multiplication: {case[0]} * {case[1]} = {result}")

    try:
        result = case[0] / case[1]
        print(f"Division: {case[0]} / {case[1]} = {result}")
    except ZeroDivisionError as e:
        print(e)

    result = case[0]**2
    print(f"Square: {case[0]}^2 = {result}")

    c = ComplexNumber.phase(math.pi / 2)
    print(f"Phase of sqrt(-1): {c}")

    result = abs(case[0])
    print(f"Modulus of {case[0]}: {result}")

这个示例展示了复数的基本操作，包括加减乘除和指数运算，以及模和相角的计算。在测试部分，我们使用了一些预定义的测试案例来验证类的行为。