CLN: Follow-up to #24100
Avoid 1-letter variable names
Modernize string formatting
Avoid an unnecessary level of indirection in add_datetimelike_methods for DTA/TDA/PA
Hello @jbrockmendel! Thanks for submitting the PR.

 - There are no PEP8 issues in the file [`pandas/core/arrays/datetimelike.py`](https://github.com/jbrockmendel/pandas/blob/98dd6b9d6b8e56312480d9342981c3d76562e179/pandas/core/arrays/datetimelike.py) !

 - There are no PEP8 issues in the file [`pandas/core/arrays/datetimes.py`](https://github.com/jbrockmendel/pandas/blob/98dd6b9d6b8e56312480d9342981c3d76562e179/pandas/core/arrays/datetimes.py) !

 - There are no PEP8 issues in the file [`pandas/core/arrays/period.py`](https://github.com/jbrockmendel/pandas/blob/98dd6b9d6b8e56312480d9342981c3d76562e179/pandas/core/arrays/period.py) !

 - There are no PEP8 issues in the file [`pandas/core/arrays/timedeltas.py`](https://github.com/jbrockmendel/pandas/blob/98dd6b9d6b8e56312480d9342981c3d76562e179/pandas/core/arrays/timedeltas.py) !

 - There are no PEP8 issues in the file [`pandas/core/frame.py`](https://github.com/jbrockmendel/pandas/blob/98dd6b9d6b8e56312480d9342981c3d76562e179/pandas/core/frame.py) !

 - There are no PEP8 issues in the file [`pandas/core/internals/construction.py`](https://github.com/jbrockmendel/pandas/blob/98dd6b9d6b8e56312480d9342981c3d76562e179/pandas/core/internals/construction.py) !

 # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/24116?src=pr&el=h1) Report
> Merging [#24116](https://codecov.io/gh/pandas-dev/pandas/pull/24116?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/aead29b745b48af0cac5fc7f677120e9a95049f4?src=pr&el=desc) will **increase** coverage by `<.01%`.
> The diff coverage is `96.19%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/24116/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/24116?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #24116      +/-   ##
==========================================
+ Coverage    92.2%    92.2%   +<.01%     
==========================================
  Files         162      162              
  Lines       51724    51715       -9     
==========================================
- Hits        47691    47685       -6     
+ Misses       4033     4030       -3
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.6% <96.19%> (ø)` | :arrow_up: |
| #single | `43.01% <35.23%> (-0.01%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/24116?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/arrays/period.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXJyYXlzL3BlcmlvZC5weQ==) | `98.46% <ø> (-0.01%)` | :arrow_down: |
| [pandas/core/arrays/timedeltas.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXJyYXlzL3RpbWVkZWx0YXMucHk=) | `87.24% <ø> (-0.03%)` | :arrow_down: |
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `96.91% <ø> (+0.11%)` | :arrow_up: |
| [pandas/core/arrays/datetimes.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXJyYXlzL2RhdGV0aW1lcy5weQ==) | `98.25% <ø> (-0.01%)` | :arrow_down: |
| [pandas/core/internals/construction.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW50ZXJuYWxzL2NvbnN0cnVjdGlvbi5weQ==) | `96.64% <100%> (+0.02%)` | :arrow_up: |
| [pandas/core/arrays/datetimelike.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXJyYXlzL2RhdGV0aW1lbGlrZS5weQ==) | `96.28% <95.5%> (-0.06%)` | :arrow_down: |
| [pandas/util/testing.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL3V0aWwvdGVzdGluZy5weQ==) | `87.41% <0%> (-0.1%)` | :arrow_down: |
| [pandas/core/internals/blocks.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW50ZXJuYWxzL2Jsb2Nrcy5weQ==) | `93.72% <0%> (ø)` | :arrow_up: |
| [pandas/core/series.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvc2VyaWVzLnB5) | `93.7% <0%> (+0.01%)` | :arrow_up: |
| ... and [1 more](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree-more) | |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/24116?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/24116?src=pr&el=footer). Last update [aead29b...43515b9](https://codecov.io/gh/pandas-dev/pandas/pull/24116?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/24116?src=pr&el=h1) Report
> Merging [#24116](https://codecov.io/gh/pandas-dev/pandas/pull/24116?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/aead29b745b48af0cac5fc7f677120e9a95049f4?src=pr&el=desc) will **increase** coverage by `<.01%`.
> The diff coverage is `96.19%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/24116/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/24116?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #24116      +/-   ##
==========================================
+ Coverage    92.2%    92.2%   +<.01%     
==========================================
  Files         162      162              
  Lines       51724    51715       -9     
==========================================
- Hits        47691    47685       -6     
+ Misses       4033     4030       -3
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.6% <96.19%> (ø)` | :arrow_up: |
| #single | `43.01% <35.23%> (-0.01%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/24116?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/arrays/period.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXJyYXlzL3BlcmlvZC5weQ==) | `98.46% <ø> (-0.01%)` | :arrow_down: |
| [pandas/core/arrays/timedeltas.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXJyYXlzL3RpbWVkZWx0YXMucHk=) | `87.24% <ø> (-0.03%)` | :arrow_down: |
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `96.91% <ø> (+0.11%)` | :arrow_up: |
| [pandas/core/arrays/datetimes.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXJyYXlzL2RhdGV0aW1lcy5weQ==) | `98.25% <ø> (-0.01%)` | :arrow_down: |
| [pandas/core/internals/construction.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW50ZXJuYWxzL2NvbnN0cnVjdGlvbi5weQ==) | `96.64% <100%> (+0.02%)` | :arrow_up: |
| [pandas/core/arrays/datetimelike.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXJyYXlzL2RhdGV0aW1lbGlrZS5weQ==) | `96.28% <95.5%> (-0.06%)` | :arrow_down: |
| [pandas/util/testing.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL3V0aWwvdGVzdGluZy5weQ==) | `87.41% <0%> (-0.1%)` | :arrow_down: |
| [pandas/core/internals/blocks.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW50ZXJuYWxzL2Jsb2Nrcy5weQ==) | `93.72% <0%> (ø)` | :arrow_up: |
| [pandas/core/series.py](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvc2VyaWVzLnB5) | `93.7% <0%> (+0.01%)` | :arrow_up: |
| ... and [1 more](https://codecov.io/gh/pandas-dev/pandas/pull/24116/diff?src=pr&el=tree-more) | |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/24116?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/24116?src=pr&el=footer). Last update [aead29b...43515b9](https://codecov.io/gh/pandas-dev/pandas/pull/24116?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 thanks!