[ProphetNet] Correct Doc string example
Author: patrickvonplaten
Pull request: yes

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Comments:
Can we have the examples take less than 119 chars (i'd even settle for 200 honestly)?

![](https://data.whicdn.com/images/163415829/original.jpg)

> Can we have the examples take less than 119 chars (i'd even settle for 200 honestly)?

Can I break lines while using `>>>` ? Or just use a smaller input text? 

> Can I break lines while using `>>>` ? Or just use a smaller input text?

You use `... ` instead of `>>> ` for the intermediate lines, but yes you can. See the [quicktour](https://github.com/huggingface/transformers/blob/master/docs/source/quicktour.rst) for an example (scroll down to "That's encouraging! You can use it on a list of sentences" since GitHub doesn't let me link a specific line in a rst file).

> Thanks :-)

My Pylinter doesn't pick up the docstring :-/ will have to find a way to fix this. Sorry for all those long lines in the docs