def reverse_search_history(self, e): # (C-r)
        self._i_search(self._history.reverse_search_history, -1, e)
Search backward starting at the current line and moving up
dataset/ETHPy150Open deanhiller/databus/webapp/play1.3.x/python/Lib/site-packages/pyreadline/modes/emacs.py/EmacsMode.reverse_search_history