[debug] Debug Heisenbug, the old school way.
# [Codecov](https://codecov.io/gh/huggingface/transformers/pull/2354?src=pr&el=h1) Report
> Merging [#2354](https://codecov.io/gh/huggingface/transformers/pull/2354?src=pr&el=desc) into [master](https://codecov.io/gh/huggingface/transformers/commit/bfe870be654a1fc54c5479f9ad0875492d9cd959?src=pr&el=desc) will **not change** coverage.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/huggingface/transformers/pull/2354/graphs/tree.svg?width=650&token=9qOlN6Hb1c&height=150&src=pr)](https://codecov.io/gh/huggingface/transformers/pull/2354?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master    #2354   +/-   ##
=======================================
  Coverage   73.32%   73.32%           
=======================================
  Files          87       87           
  Lines       14964    14964           
=======================================
  Hits        10972    10972           
  Misses       3992     3992
```



------

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> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/huggingface/transformers/pull/2354?src=pr&el=footer). Last update [bfe870b...c8c4ecd](https://codecov.io/gh/huggingface/transformers/pull/2354?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
