how to train mask model e.g Bert using WordPieceToken
# ❓ Questions & Help
When i trained a new token by WordPiece，that generized one vocab.txt file . It couldn't load in train-language-model.py ，since in source code it used bytepiece token. Is there a module out of box could save me a lot of time to do myself？ 
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**A link to original question on Stack Overflow**:

Hi! Can you load your tokenizer using

```py
from transformers import BertTokenizer

tokenizer = BertTokenizer.from_pretrained(directory_containing_vocab_txt)
```
?<|||||>> 
> 
> Hi! Can you load your tokenizer using
> 
> ```python
> from transformers import BertTokenizer
> 
> tokenizer = BertTokenizer.from_pretrained(directory_containing_vocab_txt)
> ```
> 
> ?

Hi LysandreJik,
     Great ! It works . May I ask another question-- Do you have any experience on the loss score. Generally what score should be appropriate , my loss around 1.12 is it ok?  <|||||>This really depends of your training set and what model you use, what checkpoint you use, etc. 