code: func TreePathNewFromString(path string) (*TreePath, error) {
  	cstr := C.CString(path)
  	defer C.free(unsafe.Pointer(cstr))
  	c := C.gtk_tree_path_new_from_string((*C.gchar)(cstr))
  	if c == nil {
  		return nil, nilPtrErr
  	}
  	t := &TreePath{c}
  	runtime.SetFinalizer(t, (*TreePath).free)
  	return t, nil
  }
docs: // TreePathNewFromString is a wrapper around gtk_tree_path_new_from_string().