def METHOD_NAME(self):
    """
    Get next tokens.
    """
    retry_cnt = 0
    if ControllerClient.START:
        while True:
            socket_client = socket.socket(socket.AF_INET,
                                          socket.SOCK_STREAM)
            errno = socket_client.connect_ex(
                (self.server_ip, self.server_port))
            if errno != 0:
                retry_cnt += 1
                _logger.info("Server is NOT ready, wait 10 second to retry")
                time.sleep(10)
            else:
                break
            if retry_cnt == 6:
                _logger.error(
                    "Server is NOT ready in 1 minute, please check if it start"
                )
                os._exit(errno)
    else:
        socket_client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        errno = socket_client.connect_ex((self.server_ip, self.server_port))
        if errno != 0:
            _logger.info("Server is closed")
            os._exit(0)
    socket_client.send("next_tokens".encode())
    tokens = socket_client.recv(1024).decode()
    try:
        tokens = [int(token) for token in tokens.strip("\n").split(",")]
    except ValueError:
        sys.exit()
    return tokens