Confution with return policies: preventing excessive copy on return in bindings

[yesint]

Hi, All,
I'm confused with a seemingly trivial problem. The bindings of the method, which returns a class instance by value, generate an excessive call to copy constructor:

// The method
Selection System::select(int arg);

// The binding
.def("select", &System::select, py::return_value_policy::???)
// Generates an excessive copy of Selection on return

I've tried return_value_policy::move, which seems to be the correct behavior, but the call to copy constructor is generated anyway. Am I missing something? What is the correct idiomatic way of preventing excessive copy in such cases?