def onShortcutUnindentWithBackspace(self):
        """Backspace pressed, unindent
        """
        assert self._qpart.textBeforeCursor().endswith(self.text())

        charsToRemove = len(self._qpart.textBeforeCursor()) % len(self.text())
        if charsToRemove == 0:
            charsToRemove = len(self.text())

        cursor = self._qpart.textCursor()
        cursor.setPosition(cursor.position() - charsToRemove, QTextCursor.KeepAnchor)
        cursor.removeSelectedText()
def dec_r(self, ind):
        r, c = self.row_col(ind)
        r -= 1
        if r < 0:
            r = self.nr - 1
        if r == (self.nr - 1) and c == (self.nc - 1):
            r = self.nr - 2
        return self.indx(r, c)