Missing character

Hi

during training my own model I got this error could you please help me:

step 1: bin/import_cv2.py --audio_dir ../DataBase/fa/clips --filter_alphabet data/alphabet.txt --validate_label_local tests/test_data/validate_locale_fra.py --normalize ../DataBase/fa
step2:python3.6 -u DeepSpeech.py --train_files /home/medrik/AVA/DataBase/fa/clips/train.csv --dev_files /home/medrik/AVA/DataBase/fa/clips/dev.csv --test_files /home/medrik/AVA/DataBase/fa/clips/test.csv

error while doing step2:

I STARTING Optimization

Epoch 0 | Training | Elapsed Time: 0:00:00 | Steps: 0 | Loss: 0.000000 Traceback (most recent call last):
File “DeepSpeech.py”, line 12, in
ds_train.run_script()
File “/home/medrik/AVA/DeepSpeech/training/deepspeech_training/train.py”, line 976, in run_script
absl.app.run(main)
File “/home/medrik/AVA/tmp/train/lib/python3.6/site-packages/absl/app.py”, line 300, in run
_run_main(main, args)
File “/home/medrik/AVA/tmp/train/lib/python3.6/site-packages/absl/app.py”, line 251, in _run_main
sys.exit(main(argv))
File “/home/medrik/AVA/DeepSpeech/training/deepspeech_training/train.py”, line 948, in main
train()
File “/home/medrik/AVA/DeepSpeech/training/deepspeech_training/train.py”, line 605, in train
train_loss, _ = run_set(‘train’, epoch, train_init_op)
File “/home/medrik/AVA/DeepSpeech/training/deepspeech_training/train.py”, line 571, in run_set
exception_box.raise_if_set()
File “/home/medrik/AVA/DeepSpeech/training/deepspeech_training/util/helpers.py”, line 123, in raise_if_set
raise exception # pylint: disable = raising-bad-type
File “/home/medrik/AVA/DeepSpeech/training/deepspeech_training/util/helpers.py”, line 131, in do_iterate
yield from iterable()
File “/home/medrik/AVA/DeepSpeech/training/deepspeech_training/util/feeding.py”, line 118, in generate_values
transcript = text_to_char_array(sample.transcript, Config.alphabet, context=sample.sample_id)
File “/home/medrik/AVA/DeepSpeech/training/deepspeech_training/util/text.py”, line 18, in text_to_char_array
.format(transcript, context, list(ch for ch in transcript if not alphabet.CanEncodeSingle(ch))))
ValueError: Alphabet cannot encode transcript “” while processing sample “/home/medrik/AVA/DataBase/fa/clips/common_voice_fa_20977737.wav”, check that your alphabet contains all characters in the training corpus. Missing characters are: [].

2 issues: