DOC: Improve code example for Index.get_indexer
Make code example clearer for ``Index.get_indexer``
Hello @topper-123! Thanks for updating the PR.



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

##### Comment last updated on June 19, 2018 at 08:19 Hours UTC # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/21511?src=pr&el=h1) Report
> Merging [#21511](https://codecov.io/gh/pandas-dev/pandas/pull/21511?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/9e982e18678c47c83ce2bb5932f844e2d9ee21f3?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/21511/graphs/tree.svg?width=650&src=pr&token=eZ4WkYLtcO&height=150)](https://codecov.io/gh/pandas-dev/pandas/pull/21511?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #21511   +/-   ##
=======================================
  Coverage   91.92%   91.92%           
=======================================
  Files         153      153           
  Lines       49587    49587           
=======================================
  Hits        45583    45583           
  Misses       4004     4004
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.32% <ø> (ø)` | :arrow_up: |
| #single | `41.89% <ø> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/21511?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/indexes/base.py](https://codecov.io/gh/pandas-dev/pandas/pull/21511/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy9iYXNlLnB5) | `96.62% <ø> (ø)` | :arrow_up: |

------

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> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/21511?src=pr&el=footer). Last update [9e982e1...64b87e7](https://codecov.io/gh/pandas-dev/pandas/pull/21511?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 @topper-123 Thanks!