How to realize a constructor that uses base class pointer as parameter to receive derived class pointer

[felixhjh]

class Animal {
public:
virtual ~Animal() { }
virtual std::string go(int n_times) = 0;
};

class Dog : public Animal {
public:
std::string go(int n_times) override {
std::string result;
for (int i=0; i<n_times; ++i)
result += "woof! ";
return result;
}
};

class Zoo {
public:
Animal* animal_=nullptr;
Zoo(Animal* animal) : animal_(animal){};
void call_go(){animal_->go};

}

void BindZoo(pybind11::module& m) {
pybind11::class_(m, "Zoo")

  .def(pybind11::init<Animal*>())

}

when I use python like this

dog = Dog()
zoo = Zoo(dog)

it will assert type error, However in C++ Animal* is base class pointer, use it as parameter can accept derived class pointer and call the function go to realize polymorphism