'@return: instance represented as manifest XML
@rtype: str'

def xml(self):

    if (self.notes is not None):
        return ('<platform    os="%s"    version="%s"    notes="%s"/>' % (self.os, self.version, self.notes))
    else:
        return ('<platform    os="%s"    version="%s"/>' % (self.os, self.version))
