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- [ ] closes #xxxx
- [ ] tests added / passed
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

Hello @Giftlin! Thanks for updating the PR.



Cheers ! There are no PEP8 issues in this Pull Request. :beers: 

##### Comment last updated on September 15, 2017 at 21:09 Hours UTC # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=h1) Report
> Merging [#17548](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/328c7e179b72e257e27adf92a06718fd5a40473f?src=pr&el=desc) will **decrease** coverage by `0.01%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/17548/graphs/tree.svg?width=650&height=150&src=pr&token=eZ4WkYLtcO)](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #17548      +/-   ##
==========================================
- Coverage   91.25%   91.23%   -0.02%     
==========================================
  Files         163      163              
  Lines       49606    49606              
==========================================
- Hits        45266    45257       -9     
- Misses       4340     4349       +9
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `89.01% <ø> (ø)` | :arrow_up: |
| #single | `40.19% <ø> (-0.07%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/compat/chainmap\_impl.py](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=tree#diff-cGFuZGFzL2NvbXBhdC9jaGFpbm1hcF9pbXBsLnB5) | `0% <ø> (ø)` | :arrow_up: |
| [pandas/io/gbq.py](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=tree#diff-cGFuZGFzL2lvL2dicS5weQ==) | `25% <0%> (-58.34%)` | :arrow_down: |
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `97.77% <0%> (-0.1%)` | :arrow_down: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17548?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/pandas-dev/pandas/pull/17548?src=pr&el=footer). Last update [328c7e1...07320fb](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=h1) Report
> Merging [#17548](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/328c7e179b72e257e27adf92a06718fd5a40473f?src=pr&el=desc) will **decrease** coverage by `0.01%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/17548/graphs/tree.svg?width=650&height=150&src=pr&token=eZ4WkYLtcO)](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #17548      +/-   ##
==========================================
- Coverage   91.25%   91.23%   -0.02%     
==========================================
  Files         163      163              
  Lines       49606    49606              
==========================================
- Hits        45266    45257       -9     
- Misses       4340     4349       +9
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `89.01% <ø> (ø)` | :arrow_up: |
| #single | `40.19% <ø> (-0.07%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/compat/chainmap\_impl.py](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=tree#diff-cGFuZGFzL2NvbXBhdC9jaGFpbm1hcF9pbXBsLnB5) | `0% <ø> (ø)` | :arrow_up: |
| [pandas/io/gbq.py](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=tree#diff-cGFuZGFzL2lvL2dicS5weQ==) | `25% <0%> (-58.34%)` | :arrow_down: |
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `97.77% <0%> (-0.1%)` | :arrow_down: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17548?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/pandas-dev/pandas/pull/17548?src=pr&el=footer). Last update [328c7e1...07320fb](https://codecov.io/gh/pandas-dev/pandas/pull/17548?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 Don't worry about it.  Yellow means the tests are still running.  You should only get concerned if it turns red. @gfyoung all checks have passed.  Thanks @Giftlin !