small fix in Doku
State: closed

- [x] closes #18130
- [ ] tests added / passed
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry


Labels:
name: Docs

Comments:
# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=h1) Report
> Merging [#18131](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/f7f214ba5241d84c107d318df4f85129b9ffc938?src=pr&el=desc) will **increase** coverage by `<.01%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/18131/graphs/tree.svg?src=pr&token=eZ4WkYLtcO&width=650&height=150)](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #18131      +/-   ##
==========================================
+ Coverage   91.25%   91.26%   +<.01%     
==========================================
  Files         163      163              
  Lines       50122    50122              
==========================================
+ Hits        45740    45743       +3     
+ Misses       4382     4379       -3
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `89.07% <ø> (+0.02%)` | :arrow_up: |
| #single | `40.32% <ø> (-0.06%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `97.75% <ø> (-0.1%)` | :arrow_down: |
| [pandas/io/gbq.py](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=tree#diff-cGFuZGFzL2lvL2dicS5weQ==) | `25% <0%> (-58.34%)` | :arrow_down: |
| [pandas/plotting/\_converter.py](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=tree#diff-cGFuZGFzL3Bsb3R0aW5nL19jb252ZXJ0ZXIucHk=) | `65.2% <0%> (+1.81%)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/18131?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/18131?src=pr&el=footer). Last update [f7f214b...115f6bd](https://codecov.io/gh/pandas-dev/pandas/pull/18131?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/18131?src=pr&el=h1) Report
> Merging [#18131](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/f7f214ba5241d84c107d318df4f85129b9ffc938?src=pr&el=desc) will **increase** coverage by `<.01%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/18131/graphs/tree.svg?token=eZ4WkYLtcO&height=150&width=650&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #18131      +/-   ##
==========================================
+ Coverage   91.25%   91.26%   +<.01%     
==========================================
  Files         163      163              
  Lines       50122    50122              
==========================================
+ Hits        45740    45743       +3     
+ Misses       4382     4379       -3
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `89.07% <ø> (+0.02%)` | :arrow_up: |
| #single | `40.32% <ø> (-0.06%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `97.75% <ø> (-0.1%)` | :arrow_down: |
| [pandas/io/gbq.py](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=tree#diff-cGFuZGFzL2lvL2dicS5weQ==) | `25% <0%> (-58.34%)` | :arrow_down: |
| [pandas/plotting/\_converter.py](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=tree#diff-cGFuZGFzL3Bsb3R0aW5nL19jb252ZXJ0ZXIucHk=) | `65.2% <0%> (+1.81%)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/18131?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/18131?src=pr&el=footer). Last update [f7f214b...115f6bd](https://codecov.io/gh/pandas-dev/pandas/pull/18131?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).

Thanks @derestle-htwg !