./zipformer/export.py \
  --exp-dir zipformer/exp-small \
  --use-cr-ctc 1 \
  --use-ctc 1 \
  --use-transducer 0 \
  --use-attention-decoder 0 \
  --num-encoder-layers 2,2,2,2,2,2 \
  --feedforward-dim 512,768,768,768,768,768 \
  --encoder-dim 192,256,256,256,256,256 \
  --encoder-unmasked-dim 192,192,192,192,192,192 \
  --tokens data/lang_bpe_500/tokens.txt \
  --epoch 50 \
  --avg 25