follow-up to #17943, closes #5168
State: closed

- [x] closes #5168
- [x] tests added / passed
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry


Labels:
name: Testing
description: pandas testing functions or related to the test suite
name: Error Reporting
description: Incorrect or improved errors from pandas
name: Timezones
description: Timezone data dtype

Comments:
# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/18033?src=pr&el=h1) Report
> Merging [#18033](https://codecov.io/gh/pandas-dev/pandas/pull/18033?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/8449ffd90eb07abaa76b5c17e2a7fa753dd881f8?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/18033/graphs/tree.svg?width=650&height=150&src=pr&token=eZ4WkYLtcO)](https://codecov.io/gh/pandas-dev/pandas/pull/18033?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #18033      +/-   ##
==========================================
+ Coverage   91.24%   91.25%   +<.01%     
==========================================
  Files         163      163              
  Lines       50100    50100              
==========================================
+ Hits        45714    45717       +3     
+ Misses       4386     4383       -3
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `89.06% <ø> (+0.02%)` | :arrow_up: |
| #single | `40.24% <ø> (-0.06%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/18033?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/io/gbq.py](https://codecov.io/gh/pandas-dev/pandas/pull/18033?src=pr&el=tree#diff-cGFuZGFzL2lvL2dicS5weQ==) | `25% <0%> (-58.34%)` | :arrow_down: |
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/18033?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `97.75% <0%> (-0.1%)` | :arrow_down: |
| [pandas/plotting/\_converter.py](https://codecov.io/gh/pandas-dev/pandas/pull/18033?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/18033?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/18033?src=pr&el=footer). Last update [8449ffd...b86cfd2](https://codecov.io/gh/pandas-dev/pandas/pull/18033?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/18033?src=pr&el=h1) Report
> Merging [#18033](https://codecov.io/gh/pandas-dev/pandas/pull/18033?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/8449ffd90eb07abaa76b5c17e2a7fa753dd881f8?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/18033/graphs/tree.svg?height=150&width=650&token=eZ4WkYLtcO&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/18033?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #18033      +/-   ##
==========================================
+ Coverage   91.24%   91.25%   +<.01%     
==========================================
  Files         163      163              
  Lines       50100    50100              
==========================================
+ Hits        45714    45717       +3     
+ Misses       4386     4383       -3
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `89.06% <ø> (+0.02%)` | :arrow_up: |
| #single | `40.24% <ø> (-0.06%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/18033?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/io/gbq.py](https://codecov.io/gh/pandas-dev/pandas/pull/18033?src=pr&el=tree#diff-cGFuZGFzL2lvL2dicS5weQ==) | `25% <0%> (-58.34%)` | :arrow_down: |
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/18033?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `97.75% <0%> (-0.1%)` | :arrow_down: |
| [pandas/plotting/\_converter.py](https://codecov.io/gh/pandas-dev/pandas/pull/18033?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/18033?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/18033?src=pr&el=footer). Last update [8449ffd...0b2315f](https://codecov.io/gh/pandas-dev/pandas/pull/18033?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).

can you amend the issue in the whatsnew to include #5168 as well (the issue that fixed this).
lgtm otherwise.
thanks!