如何使用一个类来扩展多个类(而不是多重继承)？

class ClassA:
    def method_a(self):
        print("This is method A")

class ClassB:
    def method_b(self):
        print("This is method B")

class ClassC:
    def __init__(self):
        self.class_a = ClassA()
        self.class_b = ClassB()

    def method_c(self):
        self.class_a.method_a()
        self.class_b.method_b()

c = ClassC()
c.method_c()  # 输出 "This is method A" 和 "This is method B"

class InterfaceA:
    def method_a(self):
        pass

class InterfaceB:
    def method_b(self):
        pass

class ClassA(InterfaceA):
    def method_a(self):
        print("This is method A")

class ClassB(InterfaceB):
    def method_b(self):
        print("This is method B")

class ClassC(InterfaceA, InterfaceB):
    def method_a(self):
        ClassA().method_a()

    def method_b(self):
        ClassB().method_b()

c = ClassC()
c.method_a()  # 输出 "This is method A"
c.method_b()  # 输出 "This is method B"