ENH: support Period.__contains__

supporting in for a Timestamp in a Period is straightforward and useful. Note that we current consider both endpoints inclusive.

In [28]: p = Period('2016',freq='M')

In [29]: p
Out[29]: Period('2016-01', 'M')

In [30]: p.start_time
Out[30]: Timestamp('2016-01-01 00:00:00')

In [31]: p.end_time
Out[31]: Timestamp('2016-01-31 23:59:59.999999999')

In [32]: p.start_time in p
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-32-b4a9c4196274> in <module>()
----> 1 p.start_time in p

TypeError: argument of type 'Period' is not iterable

[holymonson]

@jreback I’d like to submit a PR, the implement is quite simple, but first someone should decide which method name to be used.

[simonjayhawkins]

Why not decide prior to doing stuff? Discussing and settling that here seems appropriate.

That would be ideal, but PRs tend to get more review/discussion/scrutiny than issues, so opening a PR has more chance of getting things moving than bumping an issue.