[CLN] Excel Module Cleanups
- [x] closes #25271
- [x] tests added / passed
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`

# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/25275?src=pr&el=h1) Report
> Merging [#25275](https://codecov.io/gh/pandas-dev/pandas/pull/25275?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/3ab9318f2c0806a7fd38d4b4dc47bf6c3803c1e7?src=pr&el=desc) will **decrease** coverage by `<.01%`.
> The diff coverage is `100%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/25275/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/25275?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #25275      +/-   ##
==========================================
- Coverage   91.72%   91.72%   -0.01%     
==========================================
  Files         173      173              
  Lines       52831    52830       -1     
==========================================
- Hits        48458    48457       -1     
  Misses       4373     4373
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.28% <100%> (-0.01%)` | :arrow_down: |
| #single | `41.72% <50%> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/25275?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/io/excel/\_base.py](https://codecov.io/gh/pandas-dev/pandas/pull/25275/diff?src=pr&el=tree#diff-cGFuZGFzL2lvL2V4Y2VsL19iYXNlLnB5) | `92.48% <100%> (-0.04%)` | :arrow_down: |
| [pandas/io/excel/\_util.py](https://codecov.io/gh/pandas-dev/pandas/pull/25275/diff?src=pr&el=tree#diff-cGFuZGFzL2lvL2V4Y2VsL191dGlsLnB5) | `80.64% <100%> (ø)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/25275?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/25275?src=pr&el=footer). Last update [3ab9318...7bbe910](https://codecov.io/gh/pandas-dev/pandas/pull/25275?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/25275?src=pr&el=h1) Report
> Merging [#25275](https://codecov.io/gh/pandas-dev/pandas/pull/25275?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/659e0cae6be2d7ab3370cc7d8ab936bc3ee1b159?src=pr&el=desc) will **increase** coverage by `<.01%`.
> The diff coverage is `100%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/25275/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/25275?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #25275      +/-   ##
==========================================
+ Coverage   91.73%   91.73%   +<.01%     
==========================================
  Files         173      173              
  Lines       52839    52830       -9     
==========================================
- Hits        48472    48464       -8     
+ Misses       4367     4366       -1
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.29% <100%> (-0.01%)` | :arrow_down: |
| #single | `41.73% <0%> (+0.01%)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/25275?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/io/excel/\_util.py](https://codecov.io/gh/pandas-dev/pandas/pull/25275/diff?src=pr&el=tree#diff-cGFuZGFzL2lvL2V4Y2VsL191dGlsLnB5) | `78.82% <ø> (-1.83%)` | :arrow_down: |
| [pandas/io/excel/\_base.py](https://codecov.io/gh/pandas-dev/pandas/pull/25275/diff?src=pr&el=tree#diff-cGFuZGFzL2lvL2V4Y2VsL19iYXNlLnB5) | `92.48% <100%> (-0.04%)` | :arrow_down: |
| [pandas/util/testing.py](https://codecov.io/gh/pandas-dev/pandas/pull/25275/diff?src=pr&el=tree#diff-cGFuZGFzL3V0aWwvdGVzdGluZy5weQ==) | `87.66% <0%> (+0.09%)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/25275?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/25275?src=pr&el=footer). Last update [659e0ca...bcf053e](https://codecov.io/gh/pandas-dev/pandas/pull/25275?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 Hello @tdamsma! Thanks for updating the PR.







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

##### Comment last updated on February 19, 2019 at 08:33 Hours UTC Can you fix LINT issue and merge master? can you merge master @gfyoung merge when good on your end! Thanks @tdamsma !