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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 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