class MyBaseClass:
    def __init__(self):
        super().__init__()

        # Check that at least one of the methods has been overridden
        if all(getattr(self.__class__, m) is getattr(MyBaseClass, m) for m in ['method1', 'method2', 'method3']):
            raise TypeError("You must implement at least one of 'method1', 'method2', 'method3'")

    def method1(self):
        pass

    def method2(self):
        pass

    def method3(self):
        pass

class MyDerivedClass(MyBaseClass):
    def method1(self):
        print("Method1 implemented")

# This will not raise an error
d = MyDerivedClass()

class MyInvalidDerivedClass(MyBaseClass):
    pass

# This will raise a TypeError
i = MyInvalidDerivedClass()