Parse an xml.dom Node object representing a target port into this
        object.

def parse_xml_node(self, node):
        '''Parse an xml.dom Node object representing a target port into this
        object.

        '''
        super(TargetPort, self).parse_xml_node(node)
        self.port_name = node.getAttributeNS(RTS_NS, 'portName')
        return self