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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 list(self, networkipv6=None, ipv6=None):
 """List all DHCPRelayIPv6. :param: networkipv6: networkipv6 id - list all dhcprelay filtering by networkipv6 id ipv6: ipv6 id - list all dhcprelay filtering by ipv6 id :return: Following dictionary: [ { "networkipv6": <networkipv4_id>, "id": <id>, "ipv6": { "block1": <block1>, "block2": <block2>, "block3": <block3>, "block4": <block4>, "block5": <block5>, "block6": <block6>, "block7": <block7>, "block8": <block8>, "ip_formated": "<string IPv6>", "networkipv6": <networkipv6_id>, "id": <ipv6_id>, "description": "<string description>" }, ] :raise NetworkAPIException: Falha ao acessar fonte de dados """


        uri = 'api/dhcprelayv6/?'
        if networkipv6:
            uri += 'networkipv6=%s&' % networkipv6
        if ipv6:
            uri += 'ipv6=%s' % ipv6

        return self.get(uri)