'Serialize the stanza\'s XML to a string.
:param bool top_level_ns: Display the top-most namespace.
Defaults to ``False``.'

def __str__(self, top_level_ns=False):

    xmlns = (self.stream.default_ns if self.stream else u'')
    return tostring(self.xml, xmlns=xmlns, stream=self.stream, top_level=(self.stream is None))
