:return: all knows IP Address

def get_ip_addresses():
        """
        :return: all knows IP Address
        """
        LOGGER.debug("IPAddressService.get_ip_addresses")
        args = {'http_operation': 'GET', 'operation_path': ''}
        response = IPAddressService.requester.call(args)
        ret = None
        if response.rc == 0:
            ret = []
            for ipAddress in response.response_content['ipAddresses']:
                ret.append(IPAddress.json_2_ip_address(ipAddress))
        elif response.rc != 404:
            err_msg = 'IPAddressService.get_ip_addresses - Problem while getting IP Address. ' \
                      'Reason: ' + str(response.response_content) + '-' + str(response.error_message) + \
                      " (" + str(response.rc) + ")"
            LOGGER.warning(err_msg)
        return ret