Update README.md
Lines 183 - 200, fixed indentation. Line 198, replaced `tokenizer_class` with `BertTokenizer`, since `tokenizer_class` is not defined in the loop it belongs to.
# [Codecov](https://codecov.io/gh/huggingface/transformers/pull/1369?src=pr&el=h1) Report
> Merging [#1369](https://codecov.io/gh/huggingface/transformers/pull/1369?src=pr&el=desc) into [master](https://codecov.io/gh/huggingface/transformers/commit/ae50ad91ea2fedb64ecd2e7c8e2d0d4778dc03aa?src=pr&el=desc) will **increase** coverage by `0.92%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/huggingface/transformers/pull/1369/graphs/tree.svg?width=650&token=9qOlN6Hb1c&height=150&src=pr)](https://codecov.io/gh/huggingface/transformers/pull/1369?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master    #1369      +/-   ##
==========================================
+ Coverage   83.76%   84.69%   +0.92%     
==========================================
  Files          84       84              
  Lines       12596    12596              
==========================================
+ Hits        10551    10668     +117     
+ Misses       2045     1928     -117
```


| [Impacted Files](https://codecov.io/gh/huggingface/transformers/pull/1369?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [transformers/modeling\_xlnet.py](https://codecov.io/gh/huggingface/transformers/pull/1369/diff?src=pr&el=tree#diff-dHJhbnNmb3JtZXJzL21vZGVsaW5nX3hsbmV0LnB5) | `72.14% <0%> (+0.89%)` | :arrow_up: |
| [transformers/modeling\_roberta.py](https://codecov.io/gh/huggingface/transformers/pull/1369/diff?src=pr&el=tree#diff-dHJhbnNmb3JtZXJzL21vZGVsaW5nX3JvYmVydGEucHk=) | `71.22% <0%> (+5.75%)` | :arrow_up: |
| [transformers/tests/modeling\_tf\_common\_test.py](https://codecov.io/gh/huggingface/transformers/pull/1369/diff?src=pr&el=tree#diff-dHJhbnNmb3JtZXJzL3Rlc3RzL21vZGVsaW5nX3RmX2NvbW1vbl90ZXN0LnB5) | `95% <0%> (+7.5%)` | :arrow_up: |
| [transformers/modeling\_tf\_pytorch\_utils.py](https://codecov.io/gh/huggingface/transformers/pull/1369/diff?src=pr&el=tree#diff-dHJhbnNmb3JtZXJzL21vZGVsaW5nX3RmX3B5dG9yY2hfdXRpbHMucHk=) | `76.92% <0%> (+66.43%)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/huggingface/transformers/pull/1369?src=pr&el=continue).
> **Legend** - [Click here to learn more](https://docs.codecov.io/docs/codecov-delta)
> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/huggingface/transformers/pull/1369?src=pr&el=footer). Last update [ae50ad9...d1176d5](https://codecov.io/gh/huggingface/transformers/pull/1369?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
<|||||>Great, thanks for updating the README!