class Base:
    def foo(self):
        print("Base")


class A(Base):
    def foo(self):
        print("A")
        super().foo()


class B(Base):
    def foo(self):
        print("B")
        super().foo()


class C(A, B):
    def foo(self):
        print("C")
        super().foo()


class D(B, A):
    def foo(self):
        print("D")
        super().foo()


class E(C, D):
    pass


print("HEELLO")