Changed import statements in examples in DOCs
This is regarding Issue #21749

- [ ] closes #xxxx
- [ ] tests added / passed
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry
Hello @alphaCTzo7G! Thanks for updating the PR.



























 - In the file [`pandas/plotting/_misc.py`](https://github.com/pandas-dev/pandas/blob/f3ee814706a71e548ce3ecb4e9db6424c7917bcc/pandas/plotting/_misc.py), following are the PEP8 issues :

> [Line 504:80](https://github.com/pandas-dev/pandas/blob/f3ee814706a71e548ce3ecb4e9db6424c7917bcc/pandas/plotting/_misc.py#L504): [E501](https://duckduckgo.com/?q=pep8%20E501) line too long (80 > 79 characters)





##### Comment last updated on July 07, 2018 at 19:26 Hours UTC # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/21774?src=pr&el=h1) Report
> Merging [#21774](https://codecov.io/gh/pandas-dev/pandas/pull/21774?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/3be3254c06a97ffe4b73b9a55df30422ceeca36d?src=pr&el=desc) will **not change** coverage.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/21774/graphs/tree.svg?src=pr&width=650&token=eZ4WkYLtcO&height=150)](https://codecov.io/gh/pandas-dev/pandas/pull/21774?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #21774   +/-   ##
=======================================
  Coverage   91.93%   91.93%           
=======================================
  Files         160      160           
  Lines       49737    49737           
=======================================
  Hits        45724    45724           
  Misses       4013     4013
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.3% <ø> (ø)` | :arrow_up: |
| #single | `41.99% <ø> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/21774?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/sparse/series.py](https://codecov.io/gh/pandas-dev/pandas/pull/21774/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvc3BhcnNlL3Nlcmllcy5weQ==) | `95.2% <ø> (ø)` | :arrow_up: |
| [pandas/tseries/holiday.py](https://codecov.io/gh/pandas-dev/pandas/pull/21774/diff?src=pr&el=tree#diff-cGFuZGFzL3RzZXJpZXMvaG9saWRheS5weQ==) | `93.1% <ø> (ø)` | :arrow_up: |
| [pandas/io/sas/sas\_xport.py](https://codecov.io/gh/pandas-dev/pandas/pull/21774/diff?src=pr&el=tree#diff-cGFuZGFzL2lvL3Nhcy9zYXNfeHBvcnQucHk=) | `90.27% <ø> (ø)` | :arrow_up: |
| [pandas/plotting/\_core.py](https://codecov.io/gh/pandas-dev/pandas/pull/21774/diff?src=pr&el=tree#diff-cGFuZGFzL3Bsb3R0aW5nL19jb3JlLnB5) | `83.57% <ø> (ø)` | :arrow_up: |
| [pandas/core/series.py](https://codecov.io/gh/pandas-dev/pandas/pull/21774/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvc2VyaWVzLnB5) | `94.2% <ø> (ø)` | :arrow_up: |
| [pandas/io/pytables.py](https://codecov.io/gh/pandas-dev/pandas/pull/21774/diff?src=pr&el=tree#diff-cGFuZGFzL2lvL3B5dGFibGVzLnB5) | `92.48% <ø> (ø)` | :arrow_up: |
| [pandas/plotting/\_misc.py](https://codecov.io/gh/pandas-dev/pandas/pull/21774/diff?src=pr&el=tree#diff-cGFuZGFzL3Bsb3R0aW5nL19taXNjLnB5) | `38.98% <ø> (ø)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/21774?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/21774?src=pr&el=footer). Last update [3be3254...f3ee814](https://codecov.io/gh/pandas-dev/pandas/pull/21774?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 Thanks! I noticed and corrected some other inconsistent references to pandas DataStrucutres
as per comment by @jreback, while correcting the import statements.

They are in this branch: https://github.com/alphaCTzo7G/pandas/tree/correct_ref_DataStructures

Do these look ok? And should I create a separate PR? Yes, new PR is easiest to review!