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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 participant into this
        object.

        '''
        if node.getElementsByTagNameNS(RTS_NS, 'Participant').length != 1:
            raise InvalidParticipantNodeError
        self.target_component = TargetComponent().parse_xml_node(\
                node.getElementsByTagNameNS(RTS_NS, 'Participant')[0])
        return self