API: Make is_strictly_monotonic_* private
xref https://github.com/pandas-dev/pandas/pull/16555#issuecomment-305608528
Oh, adding an example to the docs as well. 1 minute. # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16576?src=pr&el=h1) Report
> Merging [#16576](https://codecov.io/gh/pandas-dev/pandas/pull/16576?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/4ec98d8b10728af9695c7e35e04b7e3fd9c408d3?src=pr&el=desc) will **not change** coverage.
> The diff coverage is `100%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/16576/graphs/tree.svg?src=pr&token=eZ4WkYLtcO&width=650&height=150)](https://codecov.io/gh/pandas-dev/pandas/pull/16576?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #16576   +/-   ##
=======================================
  Coverage   90.75%   90.75%           
=======================================
  Files         161      161           
  Lines       51089    51089           
=======================================
  Hits        46368    46368           
  Misses       4721     4721
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.59% <100%> (ø)` | :arrow_up: |
| #single | `40.16% <0%> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/16576?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/indexes/base.py](https://codecov.io/gh/pandas-dev/pandas/pull/16576?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy9iYXNlLnB5) | `95.75% <ø> (ø)` | :arrow_up: |
| [pandas/core/indexes/datetimes.py](https://codecov.io/gh/pandas-dev/pandas/pull/16576?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy9kYXRldGltZXMucHk=) | `95.33% <100%> (ø)` | :arrow_up: |

------

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> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16576?src=pr&el=footer). Last update [4ec98d8...60f3a3c](https://codecov.io/gh/pandas-dev/pandas/pull/16576?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 thanks !