This class and module cannot be found
I want to use BertForNextSentencePrediction in ' modeling_bert.py' line 1020  ,but when I run Examples in line 1065,  error happens

  File "E:\work\pycharm\transformers-master\src\transformers\tokenization_bert.py", line 24, in <module>
    from tokenizers import BertWordPieceTokenizer
ImportError: No module named 'tokenizers'

where I can find this module tokenizers,
thanks !!

You can do `pip install tokenizers` or [install from source](https://github.com/huggingface/tokenizers).<|||||>> You can do `pip install tokenizers` or [install from source](https://github.com/huggingface/tokenizers).

OK， I've got it ,thank you<|||||>> pip install tokenizers

```bash
Requirement already satisfied: tokenizers in ./anaconda3/envs/dnabert/lib/python3.6/site-packages (0.8.1rc2)
```

I did it,but it also has the error<|||||>in my another computer, the env displays its version is 0.5.0, so why give me 0.8.1rc2? sometimes i want to say, the doc is hard to understand, when understanded, the errors occurs one by one because of some small tips, is it my fault? maybe, but why not write it straightly?