class ComplexNumber(object):
    def __init__(self, real, imaginary):
        pass

    def add(self, other):
        pass

    def mul(self, other):
        pass

    def sub(self, other):
        pass

    def div(self, other):
        pass

    def abs(self):
        pass

    def conjugate(self):
        pass

    def exp(self):
        pass