def rotate(self):
        """ Rotate the kill ring, then yank back the new top.

        Returns
        -------
        A text string or None.
        """
        self._index -= 1
        if self._index >= 0:
            return self._ring[self._index]
        return None
 Rotate the kill ring, then yank back the new top.

        Returns
        -------
        A text string or None.
        
angrmanagement/vendor/qtconsole/kill_ring.py