environment/lib/python2.7/site-packages/IPython/frontend/qt/console/history_console_widget.py
def _history_locked(self):
        """ Returns whether history movement is locked.
        """
        return (self.history_lock and
                (self._get_edited_history(self._history_index) !=
                 self.input_buffer) and
                (self._get_prompt_cursor().blockNumber() !=
                 self._get_end_cursor().blockNumber()))
def _history_locked(self):
        """ Returns whether history movement is locked.
        """
        return (self.history_lock and
                (self._get_edited_history(self._history_index) !=
                 self.input_buffer) and
                (self._get_prompt_cursor().blockNumber() !=
                 self._get_end_cursor().blockNumber()))
Returns whether history movement is locked.