pip install error
Hi, I tried to install transformers library via `pip install transformers` and I got tokenizer install error.

The error logs are as follows.
```
ERROR: Could not find a version that satisfies the requirement tokenizers==0.8.1.rc1 (from transformers) (from versions: 0.0.2, 0.0.3, 0.0.4, 0.0.5, 0.0.6, 0.0.7, 0.0.8, 0.0.9, 0.0.10, 0.0.11, 0.0.12, 0.0.13, 0.1.0, 0.1.1, 0.2.0, 0.2.1, 0.3.0, 0.4.0, 0.4.1, 0.4.2, 0.5.0, 0.5.1, 0.5.2, 0.6.0, 0.7.0, 0.8.0)
ERROR: No matching distribution found for tokenizers==0.8.1.rc1 (from transformers)
```

I googled about it but I couldn't find the way to solve it.
Is there I can do to handle this issue?

Thank you.
@devJWSong, how did you solve this?<|||||>Oh, actually I didn't solve it.
I just installed downgraded version which is 2.11.0. and it worked.
I still don't know the reason but I think it is the problem from my virtual environment setting since when I tried to install the recent version in the different environment, it worked...<|||||>its error occurs to me too.... could  you give me another solution about that problems? ...<|||||>Any updates on this problem?<|||||>Try changing index-url and trusted-host in pip config.
I had same issue with the environment with index-url='http://ftp.daumkakao.com/pypi/simple' and trusted-host='ftp.daumkakao.com', but everything worked well with the environment without such config.

+)
try `pip install transformers -i https://pypi.python.org/simple`<|||||>Thank you! It worked. :)