selectRegion 
  open fun selectRegion(startOffset: <Error class: unknown class>, endOffset: <Error class: unknown class>)(source)
Selects a range of characters in the label, if the label is selectable.
See method@Gtk.Label.set_selectable. If the label is not selectable, this function has no effect. If @start_offset or
Parameters
startOffset 
start offset (in characters not bytes)
endOffset 
end offset (in characters not bytes)