How to specify the model type in train.py ?

[uehara-mech]

I tried to train the model as written in readme.
However, when I tried to specify model_type, I got an error:

$ python train_iq.py --model-type ia2q

usage: train_iq.py [-h] [--model-path MODEL_PATH] [--crop-size CROP_SIZE] [--log-step LOG_STEP] [--save-step SAVE_STEP] [--eval-steps EVAL_STEPS]
                   [--eval-every-n-steps EVAL_EVERY_N_STEPS] [--num-epochs NUM_EPOCHS] [--batch-size BATCH_SIZE] [--num-workers NUM_WORKERS]
                   [--learning-rate LEARNING_RATE] [--info-learning-rate INFO_LEARNING_RATE] [--patience PATIENCE] [--max-examples MAX_EXAMPLES] [--lambda-gen LAMBDA_GEN]
                   [--lambda-z LAMBDA_Z] [--lambda-t LAMBDA_T] [--lambda-a LAMBDA_A] [--lambda-i LAMBDA_I] [--lambda-z-t LAMBDA_Z_T] [--vocab-path VOCAB_PATH]
                   [--dataset DATASET] [--val-dataset VAL_DATASET] [--train-dataset-weights TRAIN_DATASET_WEIGHTS] [--val-dataset-weights VAL_DATASET_WEIGHTS]
                   [--cat2name CAT2NAME] [--load-model LOAD_MODEL] [--rnn-cell RNN_CELL] [--hidden-size HIDDEN_SIZE] [--num-layers NUM_LAYERS] [--max-length MAX_LENGTH]
                   [--encoder-max-len ENCODER_MAX_LEN] [--bidirectional] [--use-glove] [--embedding-name EMBEDDING_NAME] [--num-categories NUM_CATEGORIES]
                   [--dropout-p DROPOUT_P] [--input-dropout-p INPUT_DROPOUT_P] [--num-att-layers NUM_ATT_LAYERS] [--z-size Z_SIZE] [--no-image-recon] [--no-answer-recon]
                   [--no-category-space]
train_iq.py: error: unrecognized arguments: --model-type ia2q

How can I successfully specify model_type?