boost::python moving ownership on an object to C++ side

Question

I have a pure-virtual base class in C++ side, that should be extended in python side. for instance: C++ side:

class Base {
public:
    virtual void Foo() = 0;
}

class BaseWrapper : public Base, public boost::python::wrapper<Base> {
public:
    void Foo() { this->get_override("Foo")(); }
}

BOOST_PYTHON_MODULE(libmy_cpp_pro) {
    class_<BaseWrapper, boost::noncopyable>("Base").def("Foo", pure_virtual(&BaseWrapper::Foo));
}

Python side:

import libmy_cpp_pro.so

class Derived(libmy_cpp_pro.Base):
    Foo(self):
        print "770"

In addition, I got a function in C++ side that gets Base* and needs to handle the object- it gets a fully-ownership on it. for instance:

void Bar(Base* obj) {
    objList.push_back(obj)
}

Now, I have a python-API for Bar(), and I want to pass it Derived-instances in a manner that only the C++ side will handle them.

How can I do it?