Method readonly

include/pybind11/pybind11.h:2065–2067

struct property_cpp_function_classic {
    template <typename PM, must_be_member_function_pointer<PM> = 0>
    static cpp_function readonly(PM pm, const handle &hdl) {
        return cpp_function([pm](const T &c) -> const D & { return c.*pm; }, is_method(hdl));
    }

    template <typename PM, must_be_member_function_pointer<PM> = 0>
    static cpp_function read(PM pm, const handle &hdl) {