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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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()