code: func (v *TreeViewColumn) AddAttribute(renderer ICellRenderer, attribute string, column int) {
  	cstr := C.CString(attribute)
  	defer C.free(unsafe.Pointer(cstr))
  	C.gtk_tree_view_column_add_attribute(v.native(),
  		renderer.toCellRenderer(), (*C.gchar)(cstr), C.gint(column))
  }
docs: // AddAttribute() is a wrapper around gtk_tree_view_column_add_attribute().