DEPR: provide deprecations and exposure for NaTType
xref #16137
# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16146?src=pr&el=h1) Report
> Merging [#16146](https://codecov.io/gh/pandas-dev/pandas/pull/16146?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/3b80ed33e00957fec4a79cde19df66d809b5d3a7?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/16146/graphs/tree.svg?width=650&src=pr&token=eZ4WkYLtcO&height=150)](https://codecov.io/gh/pandas-dev/pandas/pull/16146?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #16146   +/-   ##
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  Coverage   90.83%   90.83%           
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  Files         159      159           
  Lines       50796    50796           
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  Hits        46143    46143           
  Misses       4653     4653
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.62% <ø> (ø)` | :arrow_up: |
| #single | `40.31% <ø> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/16146?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/tslib.py](https://codecov.io/gh/pandas-dev/pandas/pull/16146?src=pr&el=tree#diff-cGFuZGFzL3RzbGliLnB5) | `100% <ø> (ø)` | :arrow_up: |
| [pandas/\_\_init\_\_.py](https://codecov.io/gh/pandas-dev/pandas/pull/16146?src=pr&el=tree#diff-cGFuZGFzL19faW5pdF9fLnB5) | `92.3% <ø> (ø)` | :arrow_up: |

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 Currently, under the main module privacy changes table we have

> - The function union_categoricals() is now importable from pandas.api.types, formerly from pandas.types.concat (GH15998)

Do you want to add an entry for `NaTTYpe` is not importable from `pandas.api.types`? > Do you want to add an entry for NaTTYpe is not importable from pandas.api.types?
sure @jreback Have you seen the comment of @shoyer on the issue?

> The right way to use this going forward is probably type(pd.NaT). I'm not sure what the point of exposing NaTType is, given that it's a singleton. Python 2 had types.NoneType but they removed it in Python 3.

I think that makes sense, and thus it is maybe not needed to expose this publicly (we can also say to use that in the deprecation message)
 if u look at the PR that's exactly what i did it's in the deprecation message Whoops :-) 
That's what you get from rebasing instead of adding a new commit, as there was no notification of a change, I supposed it was the original state that was merged :-)