'Return the contents of the current X selection.
A keyword parameter selection specifies the name of
the selection and defaults to PRIMARY.  A keyword
parameter displayof specifies a widget on the display
to use.'

def selection_get(self, **kw):

    if ('displayof' not in kw):
        kw['displayof'] = self._w
    return self.tk.call((('selection', 'get') + self._options(kw)))
