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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 wait_time condition into
        this object.

        '''
        super(WaitTime, self).parse_xml_node(node)
        wait_time_nodes = node.getElementsByTagNameNS(RTS_NS, 'WaitTime')
        if wait_time_nodes.length != 1:
            raise InvalidParticipantNodeError
        self.wait_time = int(wait_time_nodes[0].getAttributeNS(RTS_NS,
                'waitTime'))
        return self