Sentence transformer Segmentation Fault - Pytorch 1.4.0, 2.80
## Environment info
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     Don't forget to fill out the missing fields in that output! -->
     
- `transformers` version:
- Platform: Linux
- Python version:  3.7
- PyTorch version (GPU?):  1.4 (Both)
- Tensorflow version (GPU?):
- Using GPU in script?: Yes
- Using distributed or parallel set-up in script?: Doesn't Matter

### Who can help
@LysandreJik 
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 albert, bert, GPT2, XLM: @LysandreJik 
 tokenizers: @mfuntowicz
 Trainer: @sgugger
 Speed and Memory Benchmarks: @patrickvonplaten
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 Translation: @sshleifer
 Summarization: @sshleifer
 TextGeneration: @TevenLeScao 
 examples/distillation: @VictorSanh
 nlp datasets: [different repo](https://github.com/huggingface/nlp)
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 Text Generation: @TevenLeScao
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## Information

Model I am using (Bert):

The problem arises when using:
* [ ] the official example scripts: (give details below)


## To reproduce

Steps to reproduce the behavior:

1. Open python console, with torch 1.4 installed

```python
import transformers
```

This crashes with error
```text
segementation fault
```

## Expected behavior
Works as normal without error

<!-- A clear and concise description of what you would expect to happen. -->


The only way to fix this is to force install sentencepiece==0.1.91 . The root cause is that https://github.com/huggingface/transformers/blob/v2.8.0/setup.py doesn't fix the version of sentencepiece.  

This will also be fixed by #8073 <|||||>This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.
