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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 associate_ipv6(self, id_equip, id_ipv6):
 """Associates an IPv6 to a equipament. :param id_equip: Identifier of the equipment. Integer value and greater than zero. :param id_ipv6: Identifier of the ip. Integer value and greater than zero. :return: Dictionary with the following structure: {'ip_equipamento': {'id': < id_ip_do_equipamento >}} :raise EquipamentoNaoExisteError: Equipment is not registered. :raise IpNaoExisteError: IP not registered. :raise IpError: IP is already associated with the equipment. :raise InvalidParameterError: Identifier of the equipment and/or IP is null or invalid. :raise DataBaseError: Networkapi failed to access the database. :raise XMLError: Networkapi failed to generate the XML response. """


        if not is_valid_int_param(id_equip):
            raise InvalidParameterError(
                u'The identifier of equipment is invalid or was not informed.')

        if not is_valid_int_param(id_ipv6):
            raise InvalidParameterError(
                u'The identifier of ip is invalid or was not informed.')

        url = 'ipv6/' + str(id_ipv6) + '/equipment/' + str(id_equip) + '/'

        code, xml = self.submit(None, 'PUT', url)

        return self.response(code, xml)