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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 send(self, xso):
 """ Send a single XML stream object. :param xso: Object to serialise and send. :type xso: :class:`aioxmpp.xso.XSO` :raises Exception: from any serialisation errors, usually :class:`ValueError`. Serialise the `xso` and send it over the stream. If any serialisation error occurs, no data is sent over the stream and the exception is re-raised; the :meth:`send` method thus provides strong exception safety. .. warning:: The behaviour of :meth:`send` after :meth:`abort` or :meth:`close` and before :meth:`start` is undefined. """

        with self._writer.buffer():
            xso.unparse_to_sax(self._writer)