BUG: DataFrame.asof() : Timezone Awareness / Naivety comparison TypeError (incorrect) 
- [x] closes #21194 
- [x] tests added / passed
- [x] whatsnew entry
       - modified whatsnew.v0.23.1.txt


Hello @msmarchena! Thanks for updating the PR.



 - In the file [`pandas/io/tests/test_excel.py`](https://github.com/pandas-dev/pandas/blob/a5bc90b0f93ee9cd4e45d652857978771712418d/pandas/io/tests/test_excel.py), following are the PEP8 issues :

> [Line 2193:13](https://github.com/pandas-dev/pandas/blob/a5bc90b0f93ee9cd4e45d652857978771712418d/pandas/io/tests/test_excel.py#L2193): [E722](https://duckduckgo.com/?q=pep8%20E722) do not use bare except'





##### Comment last updated on August 03, 2018 at 14:02 Hours UTC # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/21284?src=pr&el=h1) Report
> Merging [#21284](https://codecov.io/gh/pandas-dev/pandas/pull/21284?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/4274b840e64374a39a0285c2174968588753ec35?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/21284/graphs/tree.svg?token=eZ4WkYLtcO&src=pr&height=150&width=650)](https://codecov.io/gh/pandas-dev/pandas/pull/21284?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #21284   +/-   ##
=======================================
  Coverage   91.85%   91.85%           
=======================================
  Files         153      153           
  Lines       49546    49546           
=======================================
  Hits        45509    45509           
  Misses       4037     4037
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.25% <100%> (ø)` | :arrow_up: |
| #single | `41.87% <0%> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/21284?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/indexes/base.py](https://codecov.io/gh/pandas-dev/pandas/pull/21284/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy9iYXNlLnB5) | `96.61% <100%> (ø)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/21284?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/21284?src=pr&el=footer). Last update [4274b84...8441881](https://codecov.io/gh/pandas-dev/pandas/pull/21284?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 can you rebase and update can u rebase