How to globally change the PYTORCH_PRETRAINED_BERT_CACHE path
Hi, all. I don't have enough disk space under `~/` to download the pre-trained model. When I run others' experiments, I always need to change their code from
```
model = BertForQuestionAnswering.from_pretrained(args.bert_model, \
                            cache_dir=PYTORCH_PRETRAINED_BERT_CACHE'distributed_{}'.format(-1))
```
to something like
```
PYTORCH_PRETRAINED_BERT_CACHE = ELSE_WHERE
model = BertForQuestionAnswering.from_pretrained(args.bert_model, \
                            cache_dir=PYTORCH_PRETRAINED_BERT_CACHE'distributed_{}'.format(-1))
```
or
```
model = BertForQuestionAnswering.from_pretrained(args.bert_model, \
                            cache_dir=ELSE_WHERE)
```

For the convenience of those who don't have enough disk under home dir `~/`, I wonder if there is any way to globally change this `PYTORCH_PRETRAINED_BERT_CACHE` value once and for all.




Hello! You can set the environment variable `TRANSFORMERS_CACHE` to define which location should be used to store weights.<|||||>@LysandreJik Thanks. 
Just to make sure I understand your point correctly. If I run `TRANSFORMERS_CACHE=ELSE_WHERE train.sh` in cmd, are all the downloaded pretrained cache files stored under `ELSE_WHERE` rather than `~/.pytorch_pretrained_bert`?

It doesn't work for me. Specifically, I run `TRANSFORMERS_CACHE=./cache_dir bash train.sh` instead of `bash train.sh` and the cache files are still download to my HOME dir `/homes/jzhoubu/.pytorch_pretrained_bert`. Below is the log.
```
11/30/2020 23:12:36 - INFO - pytorch_pretrained_bert.tokenization -   loading vocabulary file https://s3.amazonaws.com/models.huggingface.co/bert/bert-base-uncased-vocab.txt from cache at /homes/jzhoubu/.pytorch_pretrained_bert/26bc1ad6c0ac742e9b52263248f6d0f00068293b33709fae12320c0e35ccfbbb.542ce4285a40d23a559526243235df47c5f75c197f04f37d1a0c124c32c9a084
11/30/2020 23:12:42 - INFO - pytorch_pretrained_bert.modeling -   loading archive file https://s3.amazonaws.com/models.huggingface.co/bert/bert-base-uncased.tar.gz from cache at /homes/jzhoubu/.pytorch_pretrained_bert/9c41111e2de84547a463fd39217199738d1e3deb72d4fec4399e6e241983c6f0.ae3cef932725ca7a30cdcb93fc6e09150a55e2a130ec7af63975a16c153ae2ba
11/30/2020 23:12:42 - INFO - pytorch_pretrained_bert.modeling -   extracting archive file /homes/jzhoubu/.pytorch_pretrained_bert/9c41111e2de84547a463fd39217199738d1e3deb72d4fec4399e6e241983c6f0.ae3cef932725ca7a30cdcb93fc6e09150a55e2a130ec7af63975a16c153ae2ba to temp dir /tmp/tmpwf4pab4l
```


<|||||>Ah, given your logs, it seems you're running on a very very old version (`pytorch_pretrained_bert`, which is 1+ years old). While we recommend updating to more recent versions, you should be able to obtain the same behavior by setting the `PYTORCH_PRETRAINED_BERT_CACHE` environment variable instead.

For future issues, please always complete the issue template, the information related to your environment is especially important for us to help you correctly.<|||||>This issue has been automatically marked as stale and been closed because it has not had recent activity. Thank you for your contributions.

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