Retrieve data from the clipboard on this widget’s display. The keyword argument type specifies the form in which the data is to be returned, an atom name such as 'STRING' or 'FILE_NAME'; it defaults to STRING, except on X11, where UTF8_STRING is tried first and STRING is used as a fallback. The displayof keyword argument names a widget that determines the display, and defaults to the root window of the application. This is equivalent to selection_get(selection='CLIPBOARD').