issues while modifying modeling_roberta.py file
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## Details
I need the CLS representation from RobertaForMultipleChoice

For this, I changed 
 outputs = (reshaped_logits,) + outputs[2:] 
To 
 outputs = (reshaped_logits,) + outputs[1:] 
in file https://github.com/huggingface/transformers/blob/master/src/transformers/modeling_roberta.py
since outputs[1] gives the CLS representation. 

Now to incorporate this change 
I need to import RobertaForMultipleChoice from this file  and replace "from transformers import ..." in https://github.com/huggingface/transformers/blob/master/examples/run_multiple_choice.py

to "from modeling_roberta.py import ..."

I am getting import issues 
![image](https://user-images.githubusercontent.com/19836137/76137311-8d937200-5ff8-11ea-98fc-4d361eee0b32.png)

Can somebody help in resolving this?

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     you didn't get an answer ask it here on GitHub. -->
**A link to original question on Stack Overflow**: 
That's more of a general Python question related to imports than an issue with the library, you would have more luck in trying with stack overflow.

I believe the easiest way to modify files is to clone the repository and install it in your environment as an editable:

```
git clone https://github.com/huggingface/transformers
cd transformers
pip install -e .
```

Every file modification will be directly reflected in your Python runtime (if you're on Jupyter you would need to restart your kernel for it to take effect).<|||||>Thanks a lot. 
Actually the problem was that I was appending the path (i.e src/transformers) at the end in PYTHON_PATH because of which it was loading modules from the transformers library. I added the source path at index 0 and now it is working the way I want it to work.

and thanks  @LysandreJik for the restart kernel trick. 
