BUG: unsupported type Interval when writing dataframe to excel
- [x] closes #19242 
closes #9155
- [x] whatsnew entry

# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/19244?src=pr&el=h1) Report
> Merging [#19244](https://codecov.io/gh/pandas-dev/pandas/pull/19244?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/5f6c80b5e3641ab96f747bd9967e4d58b5852814?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/19244/graphs/tree.svg?token=eZ4WkYLtcO&src=pr&width=650&height=150)](https://codecov.io/gh/pandas-dev/pandas/pull/19244?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #19244   +/-   ##
=======================================
  Coverage   91.65%   91.65%           
=======================================
  Files         150      150           
  Lines       48724    48724           
=======================================
  Hits        44658    44658           
  Misses       4066     4066
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.02% <ø> (ø)` | :arrow_up: |
| #single | `41.74% <ø> (ø)` | :arrow_up: |


------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/19244?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/19244?src=pr&el=footer). Last update [5f6c80b...8859dc5](https://codecov.io/gh/pandas-dev/pandas/pull/19244?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 Hello @cbertinato! Thanks for updating the PR.





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

##### Comment last updated on January 27, 2018 at 02:19 Hours UTC small doc string comments, and pls rebase. ping on green. Looks like the AppVeyor failures are in the parquet tests. Are those coming from the rebase? can you rebase. can you rebase. and ping on green. All green! thanks @cbertinato ! keep em coming!