DOC: to_datetime format argument examples
- [ ] closes #16669


# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17412?src=pr&el=h1) Report
> :exclamation: No coverage uploaded for pull request base (`master@9cc3333`). [Click here to learn what that means](https://docs.codecov.io/docs/error-reference#section-missing-base-commit).
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/17412/graphs/tree.svg?token=eZ4WkYLtcO&src=pr&height=150&width=650)](https://codecov.io/gh/pandas-dev/pandas/pull/17412?src=pr&el=tree)

```diff
@@            Coverage Diff            @@
##             master   #17412   +/-   ##
=========================================
  Coverage          ?   91.02%           
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  Files             ?      163           
  Lines             ?    49581           
  Branches          ?        0           
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  Hits              ?    45130           
  Misses            ?     4451           
  Partials          ?        0
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.8% <ø> (?)` | |
| #single | `40.26% <ø> (?)` | |


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> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17412?src=pr&el=footer). Last update [9cc3333...4a4bde4](https://codecov.io/gh/pandas-dev/pandas/pull/17412?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 @philipphanemann Thanks! 
(fixed the merge conflict and removed the link to "timestamp vs timespan/period" (I don't think this was a correct link)