DEPR: deprecate pd.TimeGrouper
closes #16747
# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17703?src=pr&el=h1) Report
> Merging [#17703](https://codecov.io/gh/pandas-dev/pandas/pull/17703?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/eaa5081e381e111bd7a8b7c277c12527d7ae52e4?src=pr&el=desc) will **decrease** coverage by `0.04%`.
> The diff coverage is `100%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/17703/graphs/tree.svg?token=eZ4WkYLtcO&src=pr&height=150&width=650)](https://codecov.io/gh/pandas-dev/pandas/pull/17703?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #17703      +/-   ##
==========================================
- Coverage   91.27%   91.22%   -0.05%     
==========================================
  Files         163      163              
  Lines       49760    49765       +5     
==========================================
- Hits        45416    45400      -16     
- Misses       4344     4365      +21
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `89.02% <100%> (-0.03%)` | :arrow_down: |
| #single | `40.34% <25%> (-0.07%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/17703?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/api.py](https://codecov.io/gh/pandas-dev/pandas/pull/17703?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXBpLnB5) | `100% <100%> (ø)` | :arrow_up: |
| [pandas/io/gbq.py](https://codecov.io/gh/pandas-dev/pandas/pull/17703?src=pr&el=tree#diff-cGFuZGFzL2lvL2dicS5weQ==) | `25% <0%> (-58.34%)` | :arrow_down: |
| [pandas/plotting/\_converter.py](https://codecov.io/gh/pandas-dev/pandas/pull/17703?src=pr&el=tree#diff-cGFuZGFzL3Bsb3R0aW5nL19jb252ZXJ0ZXIucHk=) | `63.38% <0%> (-1.82%)` | :arrow_down: |
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/17703?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `97.73% <0%> (-0.1%)` | :arrow_down: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17703?src=pr&el=continue).
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> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17703?src=pr&el=footer). Last update [eaa5081...3771ee2](https://codecov.io/gh/pandas-dev/pandas/pull/17703?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
