How to use the @keepkey/device-protocol/lib/messages_pb.CharacterAck function in @keepkey/device-protocol

public async sendCharacterProto(
    character: string,
    _delete: boolean,
    _done: boolean
  ): Promise {
    const characterAck = new Messages.CharacterAck();
    if (character !== "") {
      characterAck.setCharacter(character);
    } else if (_delete) {
      characterAck.setDelete(_delete);
    } else if (_done) {
      characterAck.setDone(_done);
    }
    console.assert(undefined === await this.transport.call(Messages.MessageType.MESSAGETYPE_CHARACTERACK, characterAck, DEFAULT_TIMEOUT, true, true))
  }