docs: def _erase_display(self, value):
          """
          Erases display.
          """
          if value == 0:
              # delete end of line
              self._cursor.movePosition(self._cursor.End, self._cursor.KeepAnchor)
          elif value == 1:
              # delete start of line
              self._cursor.movePosition(self._cursor.Start, self._cursor.KeepAnchor)
          else:
              # delete whole line
              self._cursor.movePosition(self._cursor.Start)
              self._cursor.movePosition(self._cursor.End, self._cursor.KeepAnchor)
          self._cursor.removeSelectedText()
          self._last_cursor_pos = self._cursor.position()